WO2016163817A1

WO2016163817A1 - Method and device for inter-device communication

Info

Publication number: WO2016163817A1
Application number: PCT/KR2016/003727
Authority: WO
Inventors: 강현정; 노상민; 아기왈아닐; 장영빈; 황준
Original assignee: 삼성전자 주식회사
Priority date: 2015-04-09
Filing date: 2016-04-08
Publication date: 2016-10-13

Abstract

The present disclosure relates to a 5G or pre-5G communication system to be provided in order to support a higher data transmission rate following 4G communication systems such as LTE. Disclosed are a method and device for improving device searching in a D2D communication system supporting direct communication between devices. The method comprises the steps of: generating a search signal including search information; selecting a transmission resource to transmit the search signal; transmitting the search signal through the selected transmission resource; and when a request signal requesting additional information on the search from a counterpart device that has received the search signal is received, transmitting a confirmation signal including the requested additional information to the counterpart device. The present disclosure relates to a communication technique and system which combine a 5G communication system, for supporting a higher data transmission rate following 4G systems, with IoT technology.

Description

Method and device for communication between devices

The present disclosure relates to a method and apparatus for discovering a counterpart device in device-to-device (D2D) communication.

4G (4 ^th -Generation) to meet the traffic demand in the radio data communication system since the increase commercialized, efforts to develop improved 5G (5 ^th -Generation) communication system or a pre-5G communication system comprises . For this reason, a 5G communication system or a pre-5G communication system is called a system after a 4G network (Beyond 4G Network) or a system after a Long Term Evolution (LTE) system (Post LTE).

In order to achieve high data rates, 5G communication systems are being considered for implementation in the ultra-high frequency (mmWave) band (e.g., 60 gigabyte (60 GHz) band). In order to mitigate the path loss of propagation and increase the propagation distance of radio waves in the ultra-high frequency band, beamforming, massive multi-input multi-output (MIMI), full-dimensional multi-input and output in 5G communication systems Full Dimensional MIMO (FD-MIMO), array antenna, analog beam-forming, and large scale antenna techniques are discussed.

In addition, in order to improve the network of the system, in the 5G communication system, an advanced small cell, an advanced small cell, a cloud radio access network (cloud RAN), an ultra-dense network ), Device to Device (D2D) communication, wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP), and incoming interference cancellation technology development such as cancellation) is underway.

In addition, in 5G systems, Hybrid FSK and QAM Modulation (FQAM) and Slide Window Superposition Coding (SWSC), Advanced Coding Modulation (ACM), and FBMC (Filter Bank Multi Carrier) and NOMA are advanced access technologies. Non orthogonal multiple access (SAP), and sparse code multiple access (SCMA) are being developed.

Meanwhile, the Internet is evolving from a human-centered connection network where humans generate and consume information, and an Internet of Things (IoT) network that exchanges and processes information among distributed components such as things. The Internet of Everything (IoE) technology is an example in which big data processing technology through connection with a cloud server is combined with IoT technology.

In order to implement the IoT, technical elements such as sensing technology, wired / wireless communication and network infrastructure, service interface technology, and security technology are required, and recently, a sensor network for connection between things, a machine to machine communication , M2M), Machine Type Communication (MTC), etc. are being studied.

In an IoT environment, intelligent IT (Internet Technology) services that create new value in human life by collecting and analyzing data generated from connected objects can be provided. IoT can be applied to the fields of smart home, smart building, smart city, smart car or connected car, smart grid, health care, smart home appliance, advanced medical service through convergence and complex of existing IT technology and various industries. have.

Accordingly, various attempts have been made to apply the 5G communication system to the IoT network. For example, a sensor network, a communication of things, an MTC, and the like are 5G communication technologies implemented by techniques such as beamforming, MIMO, and array antennas. The application of cloud radio access network as the big data processing technology described above may be an example of convergence of 5G technology and IoT technology.

The D2D communication system supports direct communication between devices in addition to communication through an enhanced Node B (eNB or Base Station) to meet ever-increasing demand for wireless data traffic and support higher data rates. do. In the D2D communication system, devices search for a counterpart device to directly communicate with or perform packet transmission / reception with the found counterpart device. According to a discovery procedure of an existing D2D communication system, each device transmits its own device information or its service information with a simple identifier. The counterpart device receiving the signal including the device identifier connects to the D2D communication server to acquire the device information or the service information. In order for the counterpart device to obtain information or service information of the device from the D2D communication server, access to the D2D communication server should be possible. When the counterpart device is outside the coverage of the cellular base station, access to the D2D communication server is impossible, and thus it is impossible to obtain the device information or the service information.

If the device within the coverage of the cellular base station can relay the base station and the external device outside the coverage of the cellular base station, the device information even if the external device outside the coverage of the cellular base station cannot access the D2D communication server. Alternatively, service information may be obtained. Therefore, a technique for searching for a device capable of performing a relay role should be provided.

On the other hand, research on vehicle-to-vehicle communication is active for the implementation of a smart car or connected car.

One embodiment of the first disclosure provides a method and apparatus for transmitting and receiving information in a communication system.

One embodiment of the first disclosure provides an apparatus and method for discovering a device, an application, a service, a group member, and a relay device in a device to device communication (D2D) system.

One embodiment of the first disclosure proposes a method and apparatus for providing an efficient discovery to a device outside cellular base station coverage in a system where a device within cellular base station coverage and a device outside cellular base station coexist.

One embodiment of the first disclosure proposes an apparatus and method for discovering a group member device without the assistance of a cellular base station in a D2D communication system.

One embodiment of the first disclosure proposes an apparatus and method for searching for a relay device providing a connection to a cellular base station in a D2D communication system.

An embodiment of the first disclosure proposes an apparatus and method for discovery between a device located outside the coverage of a cellular base station in a D2D communication system or a relay device capable of providing a network connection to devices located outside the coverage of a cellular base station. do.

An embodiment of the first disclosure proposes a discovery scheme that is optimized compared to the existing D2D communication system and applicable to various D2D communication scenarios.

Meanwhile, in the second disclosure, various emergency situations may occur while the driver is driving the vehicle, and it is necessary to promptly notify the surrounding vehicles of such emergency situation. In addition, there is a need for an efficient plan for providing various information services for vehicles in operation as well as emergency situations.

An embodiment of the second disclosure provides a method and apparatus for transmitting information of an event occurring in a device to other devices.

An embodiment of the second disclosure provides a method and apparatus for transmitting information of an event occurring in a device to other devices via direct communication between devices or via a base station.

An embodiment of the second disclosure provides a method and apparatus for indicating a manner of transmitting information of an emergency event occurring in a device to another device.

An embodiment of the second disclosure provides a method and apparatus for transmitting information on an emergency event occurring in a device separately from a non-emergency event.

An embodiment of the second disclosure provides a method and apparatus for operating a resource for transmitting information about an event occurring in a device.

A method according to an embodiment of the first disclosure is provided; A discovery method for device-to-device communication, comprising: generating a discovery signal including discovery information, selecting a transmission resource to transmit the discovery signal, and transmitting the discovery signal through the selected transmission resource And when the request signal for requesting additional information related to the search is received from the counterpart device receiving the search signal, transmitting a confirmation signal including the requested additional information to the counterpart device.

In the method, the discovery signal may include a PDCP packet including a relay device discovery indicator related to the relay device transmitting the discovery signal, a MAC packet including the relay device discovery indicator, and a physical layer including the relay device discovery identifier. And at least one of a packet and a resource allocation indicator masked by the relay device discovery indicator. In addition, the MAC packet includes a version field, a reserved field, a source field, and a destination field, wherein the version field is used to indicate a repeater search or a group member search, or one of the reserved fields. The value is used to indicate a repeater search or group member search. The dispatch field may include one of a relay device identifier, a group identifier, and an application identifier, and the destination field may include an identifier of a device or a group to receive the discovery signal.

In the method, the discovery signal may include a PDCP packet including a discovery indicator indicating a discovery for service provision by a device transmitting the discovery signal, a MAC packet including the discovery indicator, and a physical including the discovery indicator. And at least one of a layer packet, a resource allocation indicator masked by the discovery indicator, and a discovery message configured in a service layer signaling format.

In the method, the discovery signal includes an identifier indicating service information or group information provided by a device transmitting the discovery signal.

In the method, the discovery information includes at least one of a relay device identifier, a group identifier, a public land mobile network (PLMN) identifier, access point name (APN) information, and an application identifier associated with the relay device sending the discovery signal. do.

In the method, the discovery information includes at least one of a group identifier, a service identifier, and a device identifier related to the device generating the discovery signal.

The method further includes receiving a request signal from the counterpart device before transmitting the discovery signal. The request signal may include a PDCP packet including a relay device search indicator related to the relay device transmitting the discovery signal, a MAC packet including the relay device search indicator, a physical layer packet including a relay device search identifier, and the relay. And at least one of a resource allocation indicator masked by the device discovery indicator and a relay request message configured in a service layer signaling format. The request signal may include a PDCP packet including a group discovery request indicator, a MAC packet including the group discovery request indicator, a physical layer packet including a group discovery request identifier, and a resource allocation indicator masked by the group discovery request indicator. , At least one of a group discovery request message configured in a service layer signaling format.

In the method, the request signal includes at least one of a device identifier, a group identifier, a PLMN identifier, APN information, and information of a physical channel used to transmit the discovery signal associated with a device transmitting the request signal.

In the method, the additional information may include a device identifier, a group identifier, a PLMN identifier, an APN information, a service identifier, a service information, a group information, and a physical channel used for transmission of the discovery signal related to a device transmitting the discovery signal. At least one of the information.

A method according to an embodiment of the first disclosure is provided; A search method for device-to-device communication, the method comprising: receiving a search signal including search information from an external device, checking the search information obtained from the search signal, and searching for the search based on the search information; Transmitting a request signal for requesting additional information to the external device; and receiving a confirmation signal including the additional information from the external device in response to the request signal.

An apparatus according to an embodiment of the first disclosure is provided; An apparatus for performing device-to-device communication, comprising: a processor for generating a discovery signal including discovery information and selecting a transmission resource for transmitting the discovery signal, a transmitter for transmitting the discovery signal through the selected transmission resource; And a receiver configured to receive a request signal for requesting additional information related to the search from the counterpart device receiving the search signal, wherein the processor is configured to transmit a confirmation signal including the requested additional information to the counterpart device. To control.

An apparatus according to an embodiment of the first disclosure is provided; An apparatus for performing device-to-device communication, the apparatus comprising: a receiver configured to receive a search signal including search information from an external device, a processor for checking the search information obtained from the search signal, and a search required based on the search information; And a transmitter for transmitting a request signal for requesting additional information to the counterpart device, wherein the processor receives a confirmation signal including the additional information from the counterpart device in response to the request signal. . According to an embodiment of the present disclosure, a method of communicating between devices includes determining whether event information indicating the occurrence of the event is transmitted to other devices within a predetermined range within a predetermined time when an event occurs in the device; If it is determined that transmission of the event information is possible, transmitting the event information in a direct communication method between devices; and if it is impossible to transmit the event information as a result of the determination, sending the event information to the other devices via a base station. Transmitting according to a local transmission method.

The method may further include transmitting the local information according to the local transmission method, including a local transmission indicator instructing the terminal receiving the event information to transmit the event information to the base station, and the local transmission indicator. And transmitting the processed event information.

In the method, the event information is transmitted in a broadcast or unicast manner.

The method may further include including a relay indicator in the event information indicating to relay the event information to another terminal.

In the method, if the event is a predetermined emergency event, the event information is a code corresponding to the predetermined emergency event.

In the method, transmitting according to the local transmission method includes detecting an entity capable of relaying the event information to the base station, and transmitting the event information to the detected entity.

In the method, if the event is a predetermined emergency event, the event information is transmitted on a carrier corresponding to the predetermined emergency event.

In the method, a resource for transmitting the event information is determined based on at least one of a requirement of a service related to the event information, a probability of using the resource, and the number of entities that will use the resource.

The method may further include transmitting resource allocation information indicating a resource to which the event information is transmitted.

In the method, the resource allocation information is masked with an identifier or code indicating a service related to the emergency event when the event is an emergency event.

An apparatus for communicating between devices according to an embodiment of the second disclosure may include: a controller configured to determine whether, when an event occurs in a device, event information indicating the occurrence of the event can be transmitted to other devices within a predetermined range within a predetermined time; If the transmission of the event information is possible as a result of the determination, the event information is transmitted in a direct communication method between devices. If the transmission of the event information is impossible as a result of the determination, the event information is transmitted to the other devices through a base station. And a transceiver for transmitting in accordance with a local transmission scheme.

Further aspects, features and benefits as described above of certain preferred embodiments of the present disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings:

1A and 1B schematically illustrate scenarios of inter-device communication outside the coverage of a cellular base station in a D2D communication system in a first disclosure;

2 illustrates a network structure of a D2D communication system according to an embodiment of the first disclosure;

3 illustrates a protocol stack for D2D data communication according to an embodiment of the first disclosure;

4 illustrates a packet layer-specific packet format according to an embodiment of the first disclosure;

5A-5C schematically illustrate protocol stacks for processing discovery signals in a D2D communication system according to embodiments of the first disclosure;

6 is a diagram schematically illustrating an example of a MAC layer discovery packet structure in a D2D communication system according to an embodiment of the first disclosure;

7 is a diagram schematically illustrating an example of a signal flow for searching for a relay device in a D2D communication system according to an embodiment of the first disclosure;

8 is a diagram schematically showing an example of a signal flow for searching for a relay device in a D2D communication system according to another embodiment of the first disclosure;

9 is a diagram schematically illustrating an example of a signal flow for searching for a group member device in a D2D communication system according to an embodiment of the first disclosure;

10 is a diagram schematically showing an example of a signal flow for searching for a group member device in a D2D communication system according to another embodiment of the first disclosure;

11 is a diagram schematically showing an example of a signal flow for searching for a relay device in a D2D communication system according to another embodiment of the first disclosure;

12 is a diagram schematically showing an example of a signal flow for searching for a relay device in a D2D communication system according to another embodiment of the first disclosure;

FIG. 13 schematically illustrates an example of a signal flow for searching for a group member device in a D2D communication system according to another embodiment of the first disclosure; FIG.

14 is a diagram schematically illustrating an example of a signal flow for searching for a group member device in a D2D communication system according to another embodiment of the first disclosure;

15 schematically illustrates a block diagram of a D2D communication device performing D2D communication according to an embodiment of the first disclosure.

16 is a diagram illustrating a basic concept of device-to-device communication according to an embodiment of the second disclosure;

17 is a diagram illustrating a basic method of transmitting and receiving a message according to an embodiment of the second disclosure;

18A to 18C illustrate an embodiment of transmitting and receiving a V2X message by selecting a code for transmitting and receiving a V2X message according to an embodiment of the second disclosure;

19 is a diagram illustrating an embodiment of transmitting and receiving messages between terminals belonging to different base station cells according to an embodiment of the second disclosure.

20 is a diagram for explaining one embodiment of local transmission according to the embodiment of the second disclosure;

21 is a diagram for explaining another embodiment of local transmission according to the embodiment of the second disclosure;

22A to 22C are diagrams for explaining that codes used for transmitting a V2X message are classified according to a delay time required for transmitting a V2X message according to an embodiment of the second disclosure.

23 is a diagram illustrating that carriers used for transmission of a V2X message are classified according to a delay time required for transmission of a V2X message according to an embodiment of the second disclosure.

24 is a diagram illustrating message transmission and reception for an emergency service and a non-emergency service according to an embodiment of the second disclosure;

25 is a diagram illustrating an example of MAC layer signaling for V2X service support according to an embodiment of the second disclosure.

FIG. 26 is a diagram illustrating a message flow when transmitting a V2X message after masking an SA with an emergency V2X code according to an embodiment of the second disclosure; FIG.

27 is a diagram illustrating a message flow when a V2X code is transmitted after masking an SA with an emergency V2X code according to an embodiment of the second disclosure;

FIG. 28 illustrates an example of communication between V2X devices outside coverage of a cellular base station in a V2X communication system according to an embodiment of the second disclosure;

29 is a diagram illustrating a protocol layer for processing discovery signals in a V2X communication system according to an embodiment of the second disclosure;

30 is a view for explaining an example of searching for a relay device in a V2X communication system according to an embodiment of the second disclosure;

31 is a view for explaining a process of a remote device searching for a relay device in the vicinity according to the embodiment of the second disclosure;

32 is a view for explaining another example of searching for a relay device in a V2X communication system according to an embodiment of the second disclosure;

33 is a diagram illustrating a process of a remote device searching for a peripheral relay device according to an embodiment of the second disclosure;

34 is a diagram illustrating a configuration of a terminal device according to embodiments of the second disclosure;

35 is a diagram illustrating a configuration of a base station apparatus according to the embodiments of the second disclosure.

In the following description of the present disclosure, when it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present disclosure, the detailed description will be omitted. Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

Embodiments of the present disclosure described below are separated for convenience of description, but at least two or more embodiments may be combined and performed within a range that does not conflict with each other.

Terms to be described below are terms defined in consideration of functions in the embodiments of the present disclosure, which may vary according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

Embodiments of the present disclosure may be variously modified and have various embodiments, and specific embodiments will be described in detail with reference to the drawings. However, this is not intended to limit the present disclosure to specific embodiments, and it should be understood to include all changes, equivalents, and substitutes included in the spirit and technical scope of the present disclosure.

In addition, terms including ordinal numbers such as first and second may be used to describe various components, but the components are not limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present disclosure, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. The term and / or includes a combination of a plurality of related items or any item of a plurality of related items.

Also, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, "includes." Or "have." And the like are intended to indicate that there is a feature, number, step, action, component, part, or combination thereof described in the specification, and that one or more other features or numbers, step, action, component, part, or It should be understood that they do not preclude the presence or possibility of adding these in advance.

An apparatus and method proposed in the present disclosure are a Long-Term Evolution (LTE) mobile communication system, a Long-Term Evolution-Advanced (LTE-A) mobile communication system, a high-speed downlink High speed downlink packet access (HSDPA) mobile communication system, high speed uplink packet access (HSUPA) mobile communication system, and 3rd generation partnership project 2: 3GPP2. A high rate packet data (HRPD) mobile communication system, a 3GPP2 wideband code division multiple access (WCDMA) mobile communication system, and a 3GPP2 code division multiple access CDMA) mobile communication system, Institute of Electrical and Electronics Engineers (IEEE) 802.16m communication system, and evolved packet system System (EPS) and Mobile Internet Protocol (Mobile Internet Protocol: Mobile IP) system and the like can be applied to various communication systems.

Hereinafter, an embodiment of the first disclosure will be described in detail with reference to FIGS. 1 to 15.

According to various embodiments of the first disclosure, the electronic device may include a communication function. For example, the electronic device may include a smart phone, a tablet personal computer (PC), a mobile phone, a video phone, and an e-book reader (e). -book reader, desktop PC, laptop PC, netbook PC, personal digital assistant (PDA), portable Portable multimedia player (PMP, hereinafter referred to as 'PMP'), MP3 player, mobile medical device, camera, wearable device (e.g., head-mounted) Head-mounted device (HMD), for example referred to as 'HMD', electronic clothing, electronic bracelet, electronic necklace, electronic accessory, electronic tattoo, or smart watch ), Etc.

According to various embodiments of the first disclosure, the electronic device may be a smart home appliance having a communication function. For example, the smart home appliance includes a television, a digital video disk (DVD) player, an audio, a refrigerator, an air conditioner, a vacuum cleaner, an oven, Microwave oven, washer, dryer, air purifier, set-top box, TV box (e.g. Samsung HomeSyncTM, Apple TVTM, or Google TVTM), gaming console ), An electronic dictionary, a camcorder, an electronic photo frame, and the like.

According to various embodiments of the first disclosure, an electronic device may include a medical device (eg, magnetic resonance angiography (MRA) device) and a magnetic resonance imaging method. imaging: MRI (hereinafter referred to as "MRI"), computed tomography (CT) device, imaging device or ultrasound device), navigation device A global positioning system (GPS) receiver, an event data recorder (EDR), and an flight recorder (flight). data recorder: FDR (hereinafter referred to as 'FER'), automotive infotainment device, navigational electronic device (e.g., navigational navigation device, gyroscope) Or a compass), avionics, security devices, industrial or consumer robots, and the like.

According to various embodiments of the first disclosure, an electronic device includes a furniture, a part of a building / structure, an electronic board, an electronic signature receiving device, a projector, and various measurement devices (eg, including a communication function). , Water, electricity, gas or electromagnetic wave measuring devices), and the like.

According to various embodiments of the first disclosure, the electronic device may be a combination of devices as described above. In addition, it will be apparent to those skilled in the art that the electronic device according to the preferred embodiments of the first disclosure is not limited to the device as described above.

According to various embodiments of the first disclosure, a user equipment (hereinafter referred to as UE) may be an electronic device.

Further, according to various embodiments of the first disclosure, as an example, the UE may operate as a signal transmission device and a signal reception device.

An embodiment of the first disclosure proposes an apparatus and method for searching for a relay device in a D2D communication system.

Also, an embodiment of the first disclosure proposes an apparatus and method for searching for a group member device in a D2D communication system.

Hereinafter, a scenario of the D2D communication system will be described.

1A and 1B schematically illustrate possible scenarios of device-to-device communication outside the coverage of a cellular base station in a D2D communication system.

Referring to FIG. 1A, in a D2D communication system, direct communication between devices (not shown) within the coverage 100 of the cellular base station (eNB) 110 and devices outside the coverage 100 of the cellular base station 110 are shown. Direct communication between (UE1, UE2, UE3) 112, 114, 116 is possible. This situation may be referred to as an out of coverage scenario. In order to perform direct communication between the

devices

112, 114, and 116 outside the coverage 100 of the cellular base station 110, the UE1 112, the UE2 114, or the UE3 116 search for each other.

Referring to FIG. 1B, in a D2D communication system, a device (UE1) 122 in the coverage 105 of the cellular base station 110 is a relay device, and a device outside the coverage 105 of the cellular base station 110, UE2. 124 or UE3 126 or UE4 128 may perform D2D communication based on support of cellular base station 110. Such a situation may be referred to as a partial coverage scenario.

2 illustrates a network structure of a D2D communication system according to an embodiment of the first disclosure.

Referring to FIG. 2, an LTE and LTE-Advanced (LTE-A) system includes an Evolved-Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (UMTS) 225 and an Evolved Packet Core network (EPC) subsystem (EPC). 230). The EPC subsystem 230 is a full-IP system for supporting high packet transmission rate and low latency, and includes a mobility management entity (MME) 235a and a serving / packet gateway (S / PGW). 235b. The E-UTRAN 225 corresponds to an access network of an LTE system, and main components of the E-UTRAN 225 are base stations (BSs) capable of performing broadband communication with a user equipment (UE) in coverage. )-referred to as eNBs (evolved Node Bs)).

The terminal may perform D2D communication with one or more terminals in close proximity, apart from the broadband communication with the base station. The D2D method for directly communicating between devices in close proximity based on LTE is defined as ProSeimity-based Service (ProSe), and the terminal capable of ProSe communication includes a D2D including a D2D discovery signal (ie discovery information) by the ProSe application layer. It can process signals and data.

ProSe

capable terminals

205 and 215 include

ProSe applications

210 and 220, and the in-coverage terminal 205 may be supported for ProSe communication by a base station of the E-UTRAN 225. In addition, the in-coverage terminal 205 may operate as a relay terminal for the out-of-coverage terminal 215. In this case, the out of coverage terminal 215 becomes a remote terminal.

The ProSe application server 240 provides an application function according to the ProSe service. For example, the application server 240 may be PSAP (Public Safety Answering Points) or social media for commercial purposes. The application server 240 may communicate with the

terminals

205 and 215 at the application level. For example, at least some of the

terminals

205 and 215 may be members of a group related to the application server 240.

The ProSe function unit 235 becomes a reference point between the application server 240, the EPC 230, and the

terminals

205 and 215, and authorizes and configures terminals that perform discovery and direct communication. Can handle a variety of actions, such as charging.

3 illustrates a protocol stack for a D2D communication scheme according to an embodiment of the first disclosure.

Referring to FIG. 3, a protocol stack of a D2D terminal includes a physical layer (PHY Layer) 325, a MAC (Media Access Control) layer 320, a RLC (Radio Link Control) layer 315, and a PDCP (Packet). Data Convergence Protocol) layer 310, IP layer 305. The IP packet generated by the IP layer 305 is converted into an RLC Packet Datagram Unit (PDU) by the PDCP layer 310 and the RLC layer 315. The MAC layer 320 generates a MAC PDU from the RLC PDU, and the MAC PDU is loaded on the physical layer PDU by the physical layer 325 and transmitted to the counterpart terminal. The data received at the counterpart terminal is processed through the reverse flow from the sender.

4 illustrates a packet format for each protocol layer according to an embodiment of the first disclosure.

Referring to FIG. 4, the MAC layer 320 attaches a MAC header 420 to the RLC PDU (s) 425 to generate a MAC PDU 410. MAC header 420 includes version number 430, Source ID (SRC ID) 435, Destination ID (DST ID) 440, Logical Channel ID (LCID) subheader (s) ( 445). The physical layer 325 attaches a cyclic redundancy check code (CRC) 415 to the MAC PDU 410 to generate the physical layer PDU 405.

In order to support D2D communication based discovery in out of coverage and partial coverage scenarios, discovery information may be transmitted and received according to the protocol layer of FIG. 3.

5A to 5C schematically illustrate protocol stacks for processing a D2D Communication based discovery signal according to embodiments of the first disclosure.

FIG. 5A illustrates a protocol stack when a D2D discovery signal is transmitted through a physical side-link shared channel (PSSCH), which is a physical channel for D2D communication, and is processed in a PDCP layer. The ProSe protocol layer packet containing discovery information generated by the ProSe protocol layer is transmitted to the PDCP layer at the transmitting terminal A 505. The PDCP layer that receives the ProSe protocol layer packet containing the discovery information transmitted from the ProSe protocol layer includes a PDCP layer packet (ie PDCP PDU) together with the discovery information indicating that the discovery information is a relay discovery or a group member discovery. Included in, and delivered to the lower RLC / MAC / PHY layer. The physical layer frame containing the discovery information in the PHY layer is transmitted through the PSSCH.

At the receiving terminal B 510, the PDCP layer restores a PDCP layer packet (i.e., PDCP PDU) from a packet received through a lower PHY / MAC / RLC layer, and then searches for a relay device or group from the PDCP layer packet. It identifies the information indicating that it is a member device discovery and delivers discovery information (ie, ProSe protocol layer packet) extracted from the PDCP layer packet to the ProSe protocol layer.

In another embodiment, in the protocol stack of FIG. 5A, the ProSe protocol layer of the transmitting terminal A 505 may transmit a packet including information indicating that the relay device discovery or the group member device discovery is performed to a lower PDCP / RLC / MAC / PHY layer. I can deliver it. The ProSe protocol layer of the receiving terminal B 510 restores the ProSe protocol layer packet from the packet received from the lower PHY / MAC / RLC / PDCP layer, and then searches for a relay device or a group member device from the restored ProSe protocol layer packet. Extract information indicating search.

5B illustrates a protocol stack when a D2D discovery signal is transmitted through a PSSCH which is a physical channel for D2D communication and is processed in a MAC layer. The ProSe protocol layer packet containing discovery information generated by the ProSe protocol layer at the transmitting terminal A 515 is delivered to the MAC layer without processing discovery information of the first initiation in the PDCP layer. When the MAC layer receives the discovery information and confirms that the discovery information is information for relay discovery or group member discovery, the MAC layer packet includes information indicating that the relay discovery or group member discovery and the ProSe protocol layer packet are included. Create and pass to the lower PHY layer. The physical layer packet including the discovery information in the PHY layer is transmitted through the PSSCH.

At the receiving terminal B 520, the MAC layer recovers the MAC layer packet from the packet received through the lower PHY layer, and then identifies information indicating that it is a relay device search or a group member device search from the MAC layer packet. In addition, discovery information (ie, ProSe protocol layer packet) extracted from the MAC layer packet is delivered to the ProSe protocol layer.

5C illustrates a protocol stack when a D2D discovery signal is transmitted through a physical side-link discovery channel (PSCHCH), which is a physical channel for D2D discovery, and is processed in a PHY layer. The ProSe protocol layer packet containing discovery information generated by the ProSe protocol layer at the transmitting terminal A 525 is delivered to the PHY layer without processing discovery information of the first initiation in the PDCP layer or the MAC layer. When the PHY layer receives the discovery information and determines that the discovery information is information for discovery of a relay device or discovery of a group member device, the PHY layer corresponds to a ProSe protocol layer packet corresponding to a code corresponding to the discovery of a relay device or a discovery of a group member device. It transmits by assigning to PHY resource.

The PHY layer of the terminal B 530, which is the receiving side, receives a code corresponding to the discovery of the relay device or the discovery of the group member device transmitted by the PHY layer of the transmitting side. The code is passed to the ProSe protocol layer and used to confirm that the ProSe protocol layer packet includes discovery information for relay device discovery or group member device discovery.

The code corresponding to the discovery of the relay device may use the same value worldwide, the same value for each Public Land Mobile Network (PLMN), or the same value for each Access Point Name (APN). Similarly, the code corresponding to the group member device discovery may use the same value worldwide, use the same value for each PLMN, use the same value for each APN, or use a value defined for a specific service.

In another embodiment, the relay device discovery or group member device discovery information may consist of packets of a service layer or network layer format, and may be exchanged through a separate channel resource defined for the purpose of relay device discovery or group member device discovery. .

FIG. 6 is a diagram schematically illustrating a structure of a discovery packet generated at a MAC layer in a D2D communication system according to an embodiment of the first disclosure.

Referring to FIG. 6, the MAC layer packet 600 corresponding to the D2D discovery signal includes a version field 605 indicating a version number, a reserved field 610 for future use, and a D2D discovery signal. A sender field 615 indicating a sender address for transmitting the receiver, and a destination field 620 indicating a receiver address for receiving the D2D discovery signal. The version field 605 is used as an indicator for indicating a relay discovery (hereinafter referred to as a relay discovery indicator or a ProSe Relay Discovery indication). In another embodiment, the version field 605 is used as an indicator indicating group member search (hereinafter referred to as group member search indicator). For example, the version field value of the repeater discovery indicator packet is set to 'A', and the version field value of the group member discovery indicator packet is set to 'B'. In another embodiment, a value of the reserved field 610 may be used as a relay search indicator. In another embodiment, a value of the reserved field 610 may be used as a group member search indicator. For example, assuming that the reserved field 610 is 4 bits, one bit is used as a repeater search indicator and the other bit is used as a group member search indicator. In this case, setting the first bit value to 1 indicates that the packet is a repeater discovery indicator packet, and setting the second bit value to 1 uses the packet as a group member search indicator. As another example, assuming that the reserved field 610 is 4 bits, it indicates that one bit is used as a relay search indicator and a group member search indicator, and the other bit is activated when the first bit value is set to 1. If the value of the other bit is set to 0, it indicates that the relay device search indicator packet is set. If the value of the other bit is set to 1, it indicates that it is a group member search indicator packet.

The source field 615 is used as an identifier of a device for transmitting the D2D discovery signal. For example, if the device transmitting the D2D discovery signal is a relay device, the relay device identifier is included in the source field 615. As another example, the source field 615 may include an application identifier. The destination field 620 is used as an identifier of a device or a group to receive the D2D discovery signal.

In another embodiment, the MAC layer packet corresponding to the D2D discovery signal may include a version field, a source field, and a reserved field. The version field is used as a repeater navigation indicator. Alternatively, the version field is used as a group member search indicator. For example, the version field value of the repeater discovery indicator packet is set to 'A', and the version field value of the group member discovery indicator packet is set to 'B'. Or, a value of a reserved field is used as a repeater search indicator. Or, a value of a reserved field is used as a group member search indicator. For example, assuming that the reserved field 610 is 4 bits, one bit is used as a repeater search indicator and the other bit is used as a group member search indicator. In this case, setting the first bit value to 1 indicates that the packet is a repeater discovery indicator packet, and setting the second bit value to 1 uses the packet as a group member search indicator. As another example, assuming that the reserved field 610 is 4 bits, it indicates that one bit is used as a relay search indicator and a group member search indicator, and the other bit is activated when the first bit value is set to 1. If the value of the other bit is set to 0, it indicates that the relay device search indicator packet is set. If the value of the other bit is set to 1, it indicates that it is a group member search indicator packet.

When the D2D discovery signal is used for the purpose of repeater discovery, the dispatch field includes a repeater identifier or an identifier of a device searching for the repeater. When the D2D discovery signal is used for group member device discovery, the source field includes a corresponding group identifier. As another example, when the D2D discovery signal is used for the purpose of group member device discovery, the source field may include an application identifier.

In another embodiment, the MAC layer packet corresponding to the D2D discovery signal includes a version field and a reserved field for future use. The version field is used as a repeater navigation indicator. Alternatively, the version field is used as a group member search indicator. For example, the version field value of the repeater discovery indicator packet is set to 'A', and the version field value of the group member discovery indicator packet is set to 'B'. Or, a value of a reserved field is used as a repeater search indicator. Or, a value of a reserved field is used as a group member search indicator. For example, assuming that the reserved field 610 is 4 bits, one bit is used as a repeater search indicator and the other bit is used as a group member search indicator. In this case, setting the first bit value to 1 indicates that the packet is a repeater discovery indicator packet, and setting the second bit value to 1 uses the packet as a group member search indicator. As another example, assuming that the reserved field 610 is 4 bits, it indicates that one bit is used as a relay search indicator and a group member search indicator, and the other bit is activated when the first bit value is set to 1. If the value of the other bit is set to 0, it indicates that the relay device search indicator packet is set. If the value of the other bit is set to 1, it indicates that it is a group member search indicator packet.

In another embodiment, a value of a version field or a reserved field of a MAC layer packet corresponding to the D2D discovery signal may be a vehicle-to-vehicle (V2V) service message indicator or a vehicle-to-infrastructure (Vehicle). -to-infrastructure (V2I) service message indicator or vehicle-to-pedestrian (V2P) service message indicator can be used. The MAC layer packet including the vehicle to vehicle service message indicator or vehicle to infrastructure service message governor or vehicle to pedestrian service message indicator is used to carry vehicle to vehicle service or vehicle to infrastructure service or vehicle to pedestrian service information.

The D2D discovery signal may be implemented as a MAC layer header or a MAC layer subheader of the D2D communication system. Meanwhile, other discovery information required for relay device discovery or group member discovery, for example, PLMN information and APN information, may be included as a data part of a MAC layer packet to be transmitted together with the MAC layer header or MAC layer subheader. Can be.

Next, an embodiment of searching for a relay device using MAC layer signaling will be described with reference to FIGS. 7 to 8.

7 is a diagram schematically illustrating an example of a signal flow for searching for a relay device in a D2D communication system according to an embodiment of the first disclosure. Here, communication between a relay terminal (hereinafter referred to as a relay device) equipped with a ProSe protocol application is illustrated as a remote terminal (hereinafter referred to as a remote device) equipped with a ProSe protocol application.

Referring to FIG. 7, in step 705, the ProSe protocol layer of a relay device configures relay discovery information, that is, ProSe Relay Discovery Info, to notify peripheral devices that the relay device is a relay device, thereby forming an L2 layer in the modem of the relay device. To pass. The repeater discovery information includes at least one of a repeater identifier, a group identifier, a PLMN identifier, and APN information. In step 710, the relay device processes the relay discovery information received from the ProSe protocol layer through the L2 layer, generates ProSe Relay Discovery L2 signaling, and selects a transmission resource to transmit the L2 signaling. The transmission resource may be selected from a predetermined resource pool (preconfigured pool) for searching for inter-device communication. The resource pool may be coded in the device's memory by the manufacturer or determined by the system operator and provided to the device through the system information or control information. In step 715, the relay device transmits the L2 signaling through the selected transmission resource. The L2 signaling is generated to include the relay discovery indicator by the PDCP layer, or generated by the MAC layer to include the relay discovery indicator. Alternatively, the physical layer of the relay device may mask and transmit a resource allocation indicator (SA) indicating the transmission resource for transmitting the L2 signaling to the relay device discovery indicator. When the resource allocation indicator is masked with the relay device discovery indicator, a relay request message configured in a service layer signaling format may be transmitted through the transmission resource.

In step 720, the L2 layer of the remote device that receives the ProSe Relay Discovery L2 signaling transmits the relay discovery information obtained from the L2 signaling to the ProSe protocol layer. In step 725, the ProSe protocol layer confirms the relay discovery information and transmits an acknowledgment signal indicating that the relay discovery information is obtained to the L2 layer in the modem. On the other hand, if the relay discovery information acquired through the L2 signaling is not sufficient, that is, if there is additional information required by the ProSe protocol layer of the remote device, the remote device requests additional information related to the relay in step 730. Relay-Request signaling is sent to the relay device. In step 735, the relay device transmits Relay-Confirm signaling as a response to the Relay-Request. The relay-confirm signaling includes additional information necessary for the remote device and the relay device to perform relay communication. If necessary, the L2 layer of the relay device may be provided with the additional information to the ProSe protocol layer. Information additionally exchanged through the Relay-Request and Relay-Confirm signaling may include, for example, a PLMN identifier and / or APN information.

Here, an example in which ProSe Relay Discovery L2 signaling transmitted by a relay device corresponds to MAC layer L2 signaling will be described.

The ProSe Relay Discovery L2 signaling includes at least one piece of information such as a relay indicator, a relay identifier, a group identifier supported by the relay, a PLMN identifier, and APN information. The remote device may receive the ProSe Relay Discovery L2 signaling, select a relay device, and transmit Relay-Request signaling to the relay device to start the operation of establishing a connection to the network through the relay device. Relay-Request signaling may be sent even if additional information is required for the remote device to select a relay. The relay device receiving the Relay-Request signaling transmits the Relay-Confirm signaling as a response, and the Relay-Confirm signaling may include information necessary to provide connectivity between the remote device and the network.

8 is a diagram schematically illustrating an example of a signal flow for searching for a relay device in a D2D communication system according to another embodiment of the first disclosure. Here, communication between a relay terminal (hereinafter referred to as a relay device) equipped with a ProSe protocol application is illustrated as a remote terminal (hereinafter referred to as a remote device) equipped with a ProSe protocol application.

Referring to FIG. 8, in step 805, the ProSe protocol layer of a remote device configures relay request information for searching for a neighboring relay device to secure connectivity to a network, thereby forming an L2 layer in a modem of the remote device. To pass. The relay device request information includes at least one of a UE identifier, a group identifier, a relay device discovery indicator, a PLMN identifier, and APN information. In step 810, the remote device processes the relay request information received from the ProSe protocol layer through the L2 layer, generates ProSe Relay Request L2 signaling, and selects a transmission resource to transmit the L2 signaling. In step 815, the remote device transmits the L2 signaling through the selected transmission resource. The L2 signaling is generated to include the relay discovery indicator by the PDCP layer or generated by the MAC layer to include the relay discovery indicator. Alternatively, the physical layer of the relay device may mask and transmit a resource allocation indicator SA indicating the transmission resource for transmitting the L2 signaling to the relay device discovery indicator.

In step 820, the L2 layer of the relay device that has received the ProSe Relay Request L2 signaling transmits the relay device request information obtained from the L2 signaling to the ProSe protocol layer. In step 825, the ProSe protocol layer identifies the relay device request information, constructs relay discovery information indicating that the relay device is a relay device, and delivers the relay device discovery information to the L2 layer. The repeater discovery information includes at least one of a repeater identifier, a group identifier, a PLMN identifier, and APN information. In step 830, the relay device processes the relay discovery information received from the ProSe protocol layer through the L2 layer to generate ProSe Relay Discovery L2 signaling, selects a transmission resource to transmit the L2 signaling, and then selects a transmission resource through the selected transmission resource. Send L2 signaling. The L2 signaling may be generated to include a relay discovery indicator by the PDCP layer or may be generated to include a relay discovery indicator by the MAC layer. Alternatively, the physical layer of the relay device may mask and transmit a resource allocation indicator SA indicating the transmission resource for transmitting the L2 signaling to the relay device discovery indicator. When the resource allocation indicator is masked as a relay device discovery indicator, a relay request message configured in a service layer signaling format may be transmitted through the transmission resource.

In step 835, the L2 layer of the remote device that receives the ProSe Relay Discovery L2 signaling transmits the relay discovery information obtained from the L2 signaling to the ProSe protocol layer. In step 840, the ProSe protocol layer confirms the relay discovery information and transmits an acknowledgment signal indicating that the relay discovery information is obtained to the L2 layer in the modem. In step 845, the remote device selects a relay device based on the relay device discovery information and transmits a Relay-Request signaling to start an operation of establishing a connection to a network through the relay device. The Relay-Request signaling may be transmitted even when additional information is required for the remote device to select a relay device. In step 850, the relay device having received the Relay-Request signaling transmits Relay-Confirm signaling as a response, and the Relay-Confirm signaling may include additional information necessary to provide connectivity between the remote device and the network. As an example, the Relay-Confirm signaling may include information not included in the ProSe Relay Discovery L2 signaling such as PLMN identifier and / or APN information. To this end, the L2 layer of the relay device may be provided with information to be included in the Relay-Confirm signaling from the ProSe protocol layer.

Next, an embodiment of searching for a group member device using MAC layer signaling will be described with reference to FIGS. 9 to 10.

9 is a diagram schematically illustrating an example of a signal flow for searching for a group member device in a D2D communication system according to an embodiment of the first disclosure. Here, communication between remote terminals A and B equipped with ProSe protocol application (hereinafter referred to as remote device A and B) is shown. Here, the remote device B may be a device that already performs D2D communication, belongs to a group for D2D communication, or provides a specific service.

Referring to FIG. 9, in step 905, the ProSe protocol layer of the remote device B configures discovery information to be transmitted to peripheral devices to provide ProSe service, and delivers the discovery information to the L2 layer. The discovery information includes at least one of a group identifier, a service identifier, and a device identifier. In step 910, the remote device B processes the discovery information received by the ProSe protocol layer through the L2 layer, generates ProSe Discovery L2 signaling, and selects a transmission resource for transmitting the L2 signaling. In step 915, the remote device B transmits the L2 signaling through the selected transmission resource. The L2 signaling is generated to include a search indicator indicating a search for service provision in the PDCP layer or to include a search indicator in the MAC layer. Alternatively, the physical layer of the remote device B may mask and transmit a resource allocation indicator SA indicating the transmission resource for transmitting the L2 signaling to the discovery indicator. When the resource allocation indicator is masked with the discovery indicator, a discovery message configured in a service layer signaling format may be transmitted through the transmission resource.

In step 920, the L2 layer of the remote device A receiving the ProSe Discovery L2 signaling transmits discovery information obtained from the L2 signaling to the ProSe protocol layer. In step 925, the ProSe protocol layer confirms the service provision of the remote device B through the discovery information of the remote device B, and transmits an acknowledgment signal indicating that the discovery information has been obtained to the L2 layer in the modem. The remote device A utilizes the discovery information received from the remote device B to communicate with the remote device B, that is, to receive a service provided by the remote device B or to join a group of the remote device B.

If the discovery information obtained through the ProSe Discovery L2 signaling is not sufficient, in step 930, the remote device A transmits a Group-Info-Request signaling requesting additional information on the service or group to the remote device B. In step 935, the remote device B transmits Group-Info-Response signaling as a response to the Group-Info-Request. The Group-Info-Response signaling includes additional information necessary for the remote device A and the remote device B to perform ProSe communication. If necessary, the L2 layer of the remote device A may receive a request for the additional information from the ProSe protocol layer. Can be. Information additionally exchanged through the Group-Info-Request and Group-Info-Response signaling may include, for example, a service identifier, service information, and / or group information. To this end, the L2 layer of the remote device B may receive information to be included in the Group-Info-Response signaling from the ProSe protocol layer.

10 is a diagram schematically illustrating an example of a signal flow for searching for a group member device in a D2D communication system according to another embodiment of the first disclosure. Here, communication between remote terminals A and B equipped with ProSe protocol application (hereinafter referred to as remote device A and B) is shown. Here, the remote device B may be a device that already performs D2D communication, belongs to a group for D2D communication, or provides a specific service.

Referring to FIG. 10, in step 1005, the ProSe protocol layer of the remote device A configures group discovery request information for discovering peripheral devices in order to participate in communication in a specific service or a specific group. The group discovery request information is for requesting discovery information, and may include at least one of a device identifier, a group identifier, and a service identifier. In step 1010, the remote device A processes the group discovery request information received by the ProSe protocol layer through the L2 layer, generates ProSe Group Discovery Request L2 signaling, and selects a transmission resource to transmit the L2 signaling. In step 1015, the remote device A transmits the L2 signaling through the selected transmission resource. The L2 signaling is generated to include a group search request indicator indicating that signaling is a group request by the PDCP layer or generated by the MAC layer to include a group search request indicator. Alternatively, the physical layer of the remote device A may mask and transmit a resource allocation indicator SA indicating the transmission resource for transmitting the L2 signaling to the group search request indicator. When the resource allocation indicator is masked with the group discovery request indicator, a group discovery request message configured in a service layer signaling format may be transmitted through the transmission resource.

In step 1020, the L2 layer of the remote device B receiving the ProSe Group Discovery Request L2 signaling transmits the group discovery information obtained from the L2 signaling to the ProSe protocol layer. In step 1025, the ProSe protocol layer identifies the group discovery request information, configures group discovery information to be transmitted to the remote device A to provide ProSe service of the remote device B, and transfers the group discovery information to the L2 layer. The group discovery information includes at least one of a group identifier, a service identifier, and a device identifier. In step 1030, the modem of the remote device B processes the group discovery information received from the ProSe protocol layer through the L2 layer, generates ProSe Discovery L2 signaling, selects a transmission resource for transmitting the L2 signaling, and then uses the selected transmission resource. Transmit the L2 signaling. The L2 signaling may be generated to include a discovery indicator by the PDCP layer or may be generated to include a discovery indicator by the MAC layer. Alternatively, the physical layer of the relay device may mask and transmit a resource allocation indicator (SA) indicating a transmission resource for transmitting the L2 signaling to the discovery indicator. When the resource allocation indicator is masked as a discovery indicator, a discovery message configured in a service layer signaling format may be transmitted through the transmission resource.

In step 1035, the L2 layer of the remote device A receiving the ProSe Discovery L2 signaling transmits group discovery information obtained from the L2 signaling to the ProSe protocol layer. In step 1040, the ProSe protocol layer checks the group discovery information of the remote device B, and transmits an acknowledgment signal indicating that group discovery information has been obtained to the L2 layer in the modem. The remote device A utilizes the group search information received from the remote device B to communicate with the remote device B, that is, to receive a service provided by the remote device B or to join the group of the remote device B. .

If the group discovery information obtained through the ProSe Discovery L2 signaling is not sufficient, in step 1045, the remote device A transmits a Group-Info-Request signaling requesting additional information on a service or a group to the remote device B. In step 1050, the remote device B transmits Group-Info-Response signaling as a response to the Group-Info-Request. The Group-Info-Response signaling includes additional information necessary for the remote device A and the remote device B to perform ProSe communication. If necessary, the L2 layer of the remote device A may be provided with the additional information from the ProSe protocol layer. Information additionally exchanged through the Group-Info-Request and Group-Info-Response signaling may include, for example, a service identifier, service information, and / or group information.

As another embodiment, service message processing of a vehicle device, an infrastructure device, and a pedestrian device supporting vehicle to vehicle service or vehicle to infrastructure service or vehicle to pedestrian service will be described. The vehicle device may use the L2 signaling format described above to deliver a vehicle-to-vehicle service message or a vehicle-to-infrastructure service message or a vehicle-to-pedestrian service message to the other vehicle device or infrastructure device or pedestrian device.

Alternatively, the vehicle device may transmit a message transmitted from an allocated transmission resource by masking a resource allocation indicator to transmit vehicle-to-vehicle service message or vehicle-to-infrastructure service message or vehicle-to-pedestrian service message to vehicle communication service indication information. The other party may indicate the vehicle service message or the vehicle-to-infrastructure service message or the vehicle-to-pedestrian service message to the other vehicle or the infrastructure or the pedestrian.

The vehicle communication service message transmitted by the infrastructure device to the vehicle device or the pedestrian device may be configured according to at least one of the embodiments of the first disclosure. Alternatively, the vehicle communication service message transmitted by the pedestrian device to the infrastructure device or the vehicle device may be configured according to at least one of the embodiments of the first disclosure.

Next, an embodiment of searching for a relay device using a discovery identifier of a physical layer will be described with reference to FIGS. 11 to 12.

FIG. 11 is a diagram schematically illustrating an example of a signal flow for searching for a relay device in a D2D communication system according to another embodiment of the first disclosure. Here, communication between a relay terminal (hereinafter referred to as a relay device) equipped with a ProSe protocol application is illustrated as a remote terminal (hereinafter referred to as a remote device) equipped with a ProSe protocol application.

Referring to FIG. 11, in step 1105, the ProSe protocol layer of a relay device configures relay discovery information, that is, ProSe Relay Discovery ID, which informs peripheral devices that it is a relay device and transmits it to the modem of the relay device. The relay device discovery information is an identifier for identifying the relay device and may be, for example, an application ID. In step 1110, the modem of the relay device selects a transmission resource for transmitting the relay device discovery information, and in step 1115, the relay device discovery information is transmitted using a PHY channel corresponding to the selected transmission resource. The ProSe Relay Discovery ID for identifying the relay device may use the same value worldwide, the same value for each PLMN, or the same value for each APN. In step 1120, the modem of the remote device that receives the ProSe Relay Discovery ID transmits the ProSe Relay Discovery ID to the ProSe protocol layer. In step 1125, the ProSe protocol layer checks the ProSe Relay Discovery ID and transmits an acknowledgment signal indicating that the relay discovery information is obtained to the modem.

In step 1130, the modem of the remote device may transmit Relay-Request signaling to obtain information about the relay device that has transmitted the ProSe Relay Discovery ID and detailed information necessary for network connection. The Relay-Request signaling includes PHY channel information indicating a PHY channel on which the ProSe Relay Discovery ID is transmitted. In addition, the Relay-Request signaling may include at least one of an identifier, a group identifier, a PLMN identifier, and APN information of a remote device. The relay device that has received the Relay-Request signaling determines whether it is a target relay device corresponding to the Relay-Request signaling based on the PHY channel information. If the PHY channel information corresponds to the PHY channel to which the relay device has transmitted the ProSe Relay Discovery ID in step 1115, the relay device determines that it is a target relay device of the ProSe Relay Discovery ID in step 1135, and the relay device identifier. Relay-Confirm signaling including at least one of a group identifier, a PLMN identifier, APN information, and the PHY channel information is transmitted to the remote device. To this end, the modem of the relay device may receive information to be included in the Relay-Confirm signaling from the ProSe protocol layer.

12 is a diagram schematically showing an example of a signal flow for searching for a relay device in a D2D communication system according to another embodiment of the first disclosure. Here, communication between a relay terminal (hereinafter referred to as a relay device) equipped with a ProSe protocol application is illustrated as a remote terminal (hereinafter referred to as a remote device) equipped with a ProSe protocol application.

Referring to FIG. 12, in step 1205, the ProSe protocol layer of the remote device configures relay device request information to search for neighboring relay devices and transmits the relay device request information to the modem of the remote device. The relay device request information is information indicating that a relay device is requested and may be, for example, a ProSe Relay Request ID. The ProSe Relay Request ID may have the same value worldwide. In step 1210, the modem of the remote device selects a transmission resource for transmitting the ProSe Relay Request ID, and transmits the ProSe Relay Request ID through a PHY channel corresponding to the selected transmission resource in step 1215.

In step 1220, the modem of the relay device that has received the ProSe Relay Request ID transmits the ProSe Relay Request ID to the ProSe protocol layer. In step 1225, the ProSe protocol layer configures relay device discovery information indicating that the relay device is a relay device in response to the ProSe Relay Request ID and transmits the relay device discovery information to the modem. The relay device discovery information is information for identifying a relay device, and may be an application ID. The ProSe protocol layer may transmit the relay discovery information to the modem together with confirmation of the ProSe Relay Request ID.

In step 1230, the modem of the relay device selects a transmission resource to transmit a ProSe Relay Discovery ID corresponding to the relay discovery information, and transmits the ProSe Relay Discovery ID using a PHY channel corresponding to the selected transmission resource. The ProSe Relay Discovery ID may use the same value worldwide, the same value for each PLMN, or the same value for each APN.

In step 1235, the modem of the remote device that receives the ProSe Relay Discovery ID transmits the ProSe Relay Discovery ID to the ProSe protocol layer. In step 1240, the ProSe protocol layer obtains the ProSe Relay Discovery ID, and transmits a confirmation signal indicating that the ProSe Relay Discovery ID has been obtained to a modem.

In step 1245, the remote device may transmit Relay-Request signaling to obtain information about the relay device that has transmitted the ProSe Relay Discovery ID and detailed information necessary for network connection. The Relay-Request signaling includes PHY channel information indicating a PHY channel on which the ProSe Relay Discovery ID is transmitted. In addition, the Relay-Request signaling may include at least one of an identifier, a group identifier, a PLMN identifier, and APN information of a remote device. The relay device that has received the Relay-Request signaling determines whether it is a target relay device corresponding to the Relay-Request signaling based on the PHY channel information. If the PHY channel information corresponds to the PHY channel to which the relay device has transmitted the ProSe Relay Discovery ID in step 1230, the relay device determines that it is a target relay device of the ProSe Relay Discovery ID in step 1250, and identifies the relay device identifier. Relay-Confirm signaling including at least one of a group identifier, a PLMN identifier, APN information, and the PHY channel information is transmitted to the remote device. To this end, the modem of the relay device may receive information to be included in the Relay-Confirm signaling from the ProSe protocol layer.

Next, an embodiment of searching for a group member device using a discovery identifier scheme will be described with reference to FIGS. 13 to 14.

FIG. 13 is a diagram schematically illustrating an example of a signal flow for searching for a group member device in a D2D communication system according to another embodiment of the first disclosure. Here, communication between remote terminals A and B equipped with ProSe protocol application (hereinafter referred to as remote device A and B) is shown. Here, the remote device B may be a device that already performs D2D communication, belongs to a group for D2D communication, or provides a specific service.

Referring to FIG. 13, in step 1305, the ProSe protocol layer of the remote device B configures discovery information for transmitting a service or group information provided to peripheral devices, and includes a group member discovery ID (or service) including the discovery information. Pass the Discovery ID) to the modem. In step 1310, the modem of the remote device B selects a transmission resource for transmitting the Group Member Discovery ID, and in step 1315, transmits the Group Member Discovery ID through a PHY channel corresponding to the transmission resource. The Group Member Discovery ID is an identifier indicating service information or group information provided by the remote device B and may be set to the same value worldwide, the same for each PLMN, or the same value for each APN.

In step 1320, the modem of the remote device A receives the Group Member Discovery ID and transmits it to the ProSe protocol layer. The ProSe protocol layer of the remote device A determines whether to join a service or group corresponding to the Group Member Discovery ID. If it is decided to join the service or group, in step 1325 the ProSe protocol layer sends a confirmation signal to the modem.

In step 1330, the modem of the remote device A transmits Join-Request signaling to request the remote device B, which has transmitted the Group Member Discovery ID, to join the service or group. The Join-Request signaling includes PHY channel information indicating a PHY channel on which the Group Member Discovery ID is transmitted. In addition, the Join-Request signaling may include at least one of an identifier, a group identifier, a PLMN identifier, and APN information of the remote device A. Receiving the Join-Request signaling, the remote device B determines whether it is a target device corresponding to the Join-Request signaling based on the PHY channel information. If the PHY channel information corresponds to the PHY channel to which the remote device B has transmitted the Group Member Discovery ID in step 1315, the remote device B determines that it is a target device of the Join-Request signaling in step 1335, the device identifier Transmit Join-Confirm signaling including at least one of a group identifier, a PLMN identifier, APN information, and the PHY channel information to the remote device A. To this end, the modem of the remote device B may be provided with information to be included in the Join-Confirm signaling from the ProSe protocol layer.

14 is a diagram schematically illustrating an example of a signal flow for searching for a group member device in a D2D communication system according to another embodiment of the first disclosure. Here, communication between remote terminals A and B equipped with ProSe protocol application (hereinafter referred to as remote device A and B) is shown. Here, the remote device B may be a device that already performs D2D communication, belongs to a group for D2D communication, or provides a specific service.

Referring to FIG. 14, in step 1405, the ProSe protocol layer of the remote device A configures Group Member Request information for searching for a service or group desired by the remote device A, and transmits the Group Member Request information to the modem. The search information is for requesting search information. For example, the search information may be a Group Member Request ID. The Group Member Request ID may have the same value worldwide, the same value for each PLMN, or the same value for each APN. In step 1410, the modem of the remote device A selects a transmission resource for transmitting the Group Member Request ID, and in step 1415, transmits the Group Member Request ID through the PHY channel corresponding to the selected transmission resource.

In step 1420, the modem of the remote device B receiving the Group Member Request ID transmits the Group Member Request ID to the ProSe protocol layer. In step 1425, the ProSe protocol layer checks the Group Member Request ID, constructs Group Member Discovery information including discovery information on a service or group in which the remote device B participates, and delivers the information to the modem. The group member discovery information is an identifier indicating a service or a group provided by the remote device B, and may be set to the same value worldwide, the same for each PLMN, or the same value for each APN. In step 1430, the modem of the remote device B generates a Group Member Discovery ID corresponding to the group member discovery information, selects a transmission resource to transmit the Group Member Discovery ID, and performs a PHY channel corresponding to the selected transmission resource. The Group Member Discovery ID is transmitted.

In step 1435, the modem of the remote device A receiving the Group Member Discovery ID transmits the Group Member Discovery ID to the ProSe protocol layer. The ProSe protocol layer determines whether to participate in the service or group corresponding to the Group Member Discovery ID. If it is determined to join the service or group, the ProSe protocol layer sends a confirmation signal for requesting to join the service or group in step 1440. To pass.

In step 1445, the modem of the remote device A transmits Join-Request signaling to request the remote device B, which has transmitted the Group Member Discovery ID, to join the service or group. The Join-Request signaling includes PHY channel information indicating a PHY channel on which the Group Member Discovery ID is transmitted. In addition, the Join-Request signaling may include at least one of an identifier, a group identifier, a PLMN identifier, and APN information of the remote device A. Receiving the Join-Request signaling, the remote device B determines whether it is a target device corresponding to the Join-Request signaling based on the PHY channel information. If the PHY channel information corresponds to the PHY channel to which the remote device B transmits the Group Member Discovery ID in step 1430, the remote device B determines that it is a target device of the Join-Request signaling in step 1450, the device identifier Transmit Join-Confirm signaling including at least one of a group identifier, a PLMN identifier, APN information, and the PHY channel information to the remote device A. To this end, the modem of the remote device B may be provided with information to be included in the Join-Confirm signaling from the ProSe protocol layer.

15 schematically illustrates a block diagram of a D2D communication device performing D2D communication according to an embodiment of the first disclosure. The illustrated D2D communication device may operate as the aforementioned relay device or a remote device.

Referring to FIG. 15, a D2D communication device includes a processor 1500, a transmitter 1505, a receiver 1510, and a memory 1515.

The processor 1500 operates in accordance with at least one of the embodiments of the first disclosure described above. As an example, the processor 1500 generates L2 signaling or a physical layer frame for discovery and transmits the same through the transmitter 1505. The receiver 1510 may receive the relay request signaling, the group information request signaling, or the participation request signaling and transmit the relay request signaling to the processor 1500. The processor 1500 may transmit the additional information necessary for the request signaling in response to the request signaling. Send it through. The memory 1515 may store program codes, parameters, data, etc. necessary for the operation of the processor 1500.

At least one of the embodiments of the first disclosure has an effect of enabling the D2D communication system to efficiently search for a relay device that provides network connectivity to a device outside the coverage of the cellular base station.

In addition, at least one of the embodiments of the first disclosure has the effect of providing an optimized search function to a device outside the coverage of the cellular base station in the D2D communication system.

Hereinafter, embodiments of the second disclosure will be described.

The following description is based on the premise that the V2X communication system, but this is for convenience of description only, and is not limited to the content and scope of the present disclosure V2X communication system, the field to which the Internet of Things technology can be applied in general Applicable to In addition, although the various embodiments described herein are described separately, various embodiments may be implemented in combination unless the embodiments are expressly inconsistent with each other or conflict.

Prior to the detailed description of the embodiments of the second disclosure, the main concepts of the second disclosure are briefly described.

The second disclosure is for notifying other devices when any event occurs in the device. In particular, when a situation such as an accident or an emergency occurs while the vehicle is driving, a method for notifying the situation directly to another vehicle or via a base station is proposed. Specifically, if an event occurring in a device, in particular, a terminal of the vehicle can be transmitted to devices within a predetermined coverage within a predetermined time, it is transmitted in a direct communication method between terminals, and if it is difficult to transmit to the devices, communication via a base station Transmit in such a way.

Prior to the detailed description of the second disclosure, key terms used herein will be described.

The "device" is an object capable of supporting the Internet of Things or V2X communication, and may be, for example, an in-vehicle communication device or a smartphone. It may be referred to herein as a "terminal" or "device."

"RSU (road side unit)" is installed around the road and serves to relay the terminal and the base station, for example, it is installed together with the traffic flow collection device, street lights, traffic lights, and can communicate with the terminal. . However, in some cases, the RSU may perform a function of the terminal.

The "event" particularly refers to various situations that occur while the vehicle is running. For example, an incident that can notify the surrounding vehicle of the situation, such as a collision accident in front of the driver, unauthorized crossing of a pedestrian, or the progress of an emergency vehicle. Some of the events may be predetermined as an emergency situation or an emergency event.

"Event information" refers to information that informs the creation of the event and the content of the event. In the present specification, since the V2X communication system is described as an example, the V2X message may be an example of the event information.

FIG. 16 is a diagram illustrating a basic concept of device-to-device communication according to an embodiment of the second disclosure.

(a) is a schematic diagram for the basic concept of device-to-device communication, and (b) shows the actual vehicle driving environment.

The terminal 1 101 and the terminal 2 102 are vehicles or RSUs or user devices supporting the V2X communication service, and the RSU 110 supports the V2X communication service. The V2X server 109 is a server that supports V2X communication services. The terminal 1 101 and the terminal 2 102 may communicate with each other for a V2X service using a device-to-device (D2D) without passing through the RSU 110. The terminal 1 101 and the terminal 2 102 may be connected to the V2X server 109 via the RSU 110 to obtain information of a V2X message.

Referring to (a) and (b), the terminal 1 101 informs the terminal 2 102 or the terminal 3 103 of the event or any information issued to the terminal through direct communication between the terminals, or RSU ( Inform via 110).

First, a case of performing direct communication between terminals will be described. For example, when the terminal 1 101 detects an emergency A such as an accident occurring ahead, the terminal 1 101 transmits a time limit for transmitting a V2X message for notifying the neighboring terminals of the emergency A. Determine the required transmission coverage (X km). The transmission time limit is a maximum allowable time for which the V2X message should be transmitted. The time may vary depending on the type of emergency situation A, and may generally be several tens of msec. Transmission coverage is the minimum distance that the V2X message informing of the emergency A should be delivered. The transmission time limit and transmission coverage are information previously received from the server 109 or stored in the terminal 1 101 in advance.

When the terminal 1 101 determines that the V2X message can be notified to all the terminals in the transmission coverage within the transmission time limit through the direct communication between the terminals in consideration of the transmission time limit and the transmission coverage of the emergency situation A, the terminal 1 101 ) Transmits a V2X message to other terminals through direct communication between terminals. That is, terminal 1 101 first transmits a V2X message to terminal 2 102, and terminal 2 102 will transmit to neighboring terminals.

If it is determined that the V2X message cannot notify all the terminals in the transmission coverage within the transmission time limit through the direct communication between the terminals, the terminal 1 101 includes a "local transmission indicator" in the V2X message. It can transmit to the terminal 2 (102). The local transmission indicator is a request for the terminal receiving the V2X message to transmit it to the RSU (110). Whether to include the local transmission indicator may be determined by the transmission power, modulation or code rate of the terminal 1 (101), availability of HARQ, and the like. Terminal 2 (102) receiving the V2X message transfers the V2X message to the base station (107). The terminal 2 102 uses a preconfigured receiving resource to receive the emergency V2X message.

Upon receiving the V2X message including the local transmission indicator, the RSU 110 directly processes the V2X message. The RSU 110 searches for V2X content corresponding to the V2X message, and if the V2X message corresponds to an emergency message, generates the V2X content message including the emergency V2X content and transmits the generated V2X content message to terminals within cell coverage. In FIG. 16, it is shown as being transmitted to the terminal 2 102. Terminal 2 (102) receives the V2X message to know that the emergency A has occurred, and accordingly performs an operation corresponding to the emergency A. An example of the operation corresponding to the emergency situation A is to generate a warning sound to the driver. The V2X message and the V2X content message transmitted and received between the RSU 110 and the terminals may be transmitted in a broadcast or unicast format in the format of an RRC message or a user-plane message (PDCP, RLC, MAC message). In addition, the V2X content message may be transmitted through a physical channel, a broadcast channel, or a downlink scheduling channel for V2X. On the other hand, the mapping information between the V2X message and the V2X content is globally-specific or PLMN-specific information.

As another example, the terminal 1 101 may transmit a relay indicator including a relay indicator in the emergency V2X message. The relay indicator is a message requesting to relay the corresponding message to another terminal, and the RSU 110, the RSU 110, and the terminal receiving the relay indicator forward V2X content corresponding to the received V2X message to another terminal. do. The relay indicator may be determined by a transmission power, a modulation scheme or a code rate of the transmitting terminal, whether HARQ is applicable, and the like. The V2X content corresponding to the V2X message including the relay indicator is relayed by the RSU 110 or the RSU 110 or another terminal.

Meanwhile, when the terminal generating the V2X message is outside the coverage of the RSU 110, the V2X message transmitted by the terminal may include both a relay indicator and a local forwarding indicator. The V2X content corresponding to the V2X message including both the indicators is transmitted to the RSU 110 by the RSU 110 or another terminal having a relay function. Thereafter, the RSU 110 transmits the corresponding V2X content to another terminal within the coverage of the RSU 110 using a local forwarding function.

17 is a diagram illustrating a basic method of transmitting and receiving a message according to an embodiment of the second disclosure.

In step 201, the terminal 1 101 determines the transmission time limit and the transmission coverage for the emergency situation A. FIG. In step 203, the terminal 1 101 selects a V2X code transmission resource from a preconfigured set, and transmits an emergency V2X code to the terminal 2 102. Here, the terminal 2 102 uses a predetermined reception resource in a preconfigured code set for receiving the emergency V2X code. In step 205, the terminal 2 102 transmits the V2X code to the base station 107 using WAN resources. In step 207, the base station 107 analyzes the V2X code, retrieves V2X content mapped to the V2X code from a pre-stored mapping table, and includes emergency V2X content if the V2X content corresponding to the V2X code is emergency V2X content. Create a message. In step 207, the base station 107 transmits a message including the emergency V2X content to the terminal 2 102 using a WAN resource. In operation 211, the terminal 2 102 may know that the emergency situation A has occurred from the received message, and performs an operation corresponding to the emergency situation A, for example, generating an alert sound to the driver.

The V2X message and the V2X content message transmitted and received between the base station 107 and the terminals may be transmitted in a broadcast or unicast format in the format of an RRC message or a user-plane message (PDCP, RLC, MAC message). In addition, the V2X content message may be transmitted through a physical channel, a broadcast channel, or a downlink scheduling channel for V2X. Meanwhile, mapping information between the V2X message and the V2X content is globally-specific or PLMN-specific information. That is, the mapping information may be used uniquely in all countries or uniquely in the same PLMN.

18A to 18C are diagrams illustrating an embodiment of transmitting and receiving a V2X message by selecting a code for transmitting and receiving a V2X message according to an embodiment of the second disclosure.

FIG. 18A is a schematic diagram of device-to-device communication, FIG. 18B shows the actual vehicle driving environment, and FIG. 18C shows the message flow between entities.

In step 301, the terminal 1 101 determines the transmission time limit and the transmission coverage for the emergency situation A. FIG. As a result of the determination, it is determined that direct communication between the terminals is to be performed. In step 303, the terminal 1 101 selects a code for transmitting a V2X message from a preconfigured code resource set, and selects an emergency V2X message using the selected code. 102). The emergency V2X message may be transmitted in a broadcast or unicast manner. Here, the terminal 2 102 uses a predetermined reception code from a preconfigured code resource set for receiving the emergency V2X message. In step 305, the terminal 2 102 transmits the V2X message to the base station 107 using WAN resources to query the information of the V2X message. The information in the V2X message is a V2X application code. In step 307, the base station 107 analyzes the V2X message, retrieves V2X content mapped to the V2X code from a pre-stored mapping table, and generates a message including an emergency V2X code if the V2X message corresponds to an emergency V2X message. do. In step 309, the base station 107 transmits a message including the emergency V2X code to the terminal 2 102 using a WAN resource and responds to the query in step 307. The message used in the inquiry in step 307 and the response in step 309 may be an RRC message or a MAC message (MAC CE for V2X) or a user plane packet. The user plane packet has a new PDCP header to identify the V2X and the typical IP packet.

In operation 311, the terminal 2 102 may know that an emergency A has occurred from the received message, and performs an operation corresponding to the emergency A, for example, generating an alert sound to the driver.

For reference, the mapping information between the V2X code and the V2X content is globally-specific or PLMN-specific information. That is, the mapping information may be used uniquely in all countries or uniquely in the same PLMN.

(a) is a schematic diagram of device-to-device communication, and (b) shows an actual vehicle driving environment.

Referring to (a) and (b), it is assumed that each of the first base station 107 and the second base station includes the function of the V2X server. Accordingly, each base station has a mapping table between V2X application code and V2X information.

First, in step 403, the terminal 1 101 located in the coverage of the first base station 107 transmits a V2X message to the terminal 2 102 located in the second base station 108. The V2X message may be transmitted in a broadcast or unicast manner. In step 405, the terminal 2 101 inquires the information of the V2X message from the second base station 108. The information of the V2X message may be a V2X application code. However, since the terminal 1 101 is a terminal located within the coverage of the first base station 107, the second base station 108 may not know the information of the V2X message transmitted by the terminal 1 101. Therefore, in step 407, the second base station 108 signals the first base station 107 to query the V2X message received from the terminal 2 102. The first base station 107 can know the information of the V2X message transmitted by the terminal 1 (101) from the mapping table between the prestored V2X application code and the V2X information by using the function of the V2X server it has, step 409 In the first base station 107 transmits a response to the information of the V2X message to the second base station 108. In step 411, the second base station 108 transmits the information of the V2X message to the terminal 2 101 using the response received in step 409. Upon receipt of the response from the second base station 108, the terminal 2 101 may know that the information of the V2X message, for example, an emergency V2X message, may perform an operation corresponding to the emergency V2X message.

For reference, in

steps

405 and 411, the message used in the inquiry / response between the terminal 2 101 and the second base station 108 may be an RRC message or a MAC message (MAC CE for V2X) or a user plane packet. have. The user plane packet has a new PDCP header to identify the V2X and the typical IP packet.

Hereinafter, embodiments of the local transmission described with reference to FIG. 16 will be described.

As described above, when the UE transmits a V2X message to other terminals when the terminal determines that the message will not be transmitted to the terminals within the transmission coverage range for a transmission time limit, the base station covers the V2X message. It is a method of transmitting to the terminals in the. In the local transmission scheme, the terminal includes a local transmission indicator in the V2X message. The local transmission indicator may use a direct communication resource allocated for a V2X message through a V2X direct communication resource or may be included in a resource allocated for a V2X message through a WAN communication resource. For reference, the WAN communication refers to cellular communication between the base station and the terminal.

The other terminal (vehicle or RSU) that has received the local transmission indicator sent by an arbitrary terminal transmits the V2X message to the base station without relaying the other terminal. When the base station receives a V2X message or resource allocation for a V2X message, the base station may know that the V2X message requires local transmission. In order to know whether the V2X message requires local transmission, the base station monitors both the V2X message and the cellular communication and the V2X direct communication of the terminal. To this end, the local transmission indicator may be included in the V2X message of the V2X direct communication of the terminal. In addition, the base station receives the packet of the terminal using the cellular communication method in the cellular communication interval.

As described above, in addition to the method of including the local transmission indicator in the V2X message, there may be various methods of transmitting the local transmission indicator to the base station.

For example, when the terminal requests the V2X direct communication resource to the base station, the terminal may transmit a local transmission indicator to the base station through signaling for the V2X direct communication resource request. As another example, when the terminal requests a cellular communication resource for V2X message transmission to the base station, the terminal may transmit a local transmission indicator to the base station through the cellular communication signaling. As another example, the base station may monitor the V2X direct communication resources. If the base station receives a V2X message including a local transmission indicator, the base station transmits the V2X message to another terminal.

Meanwhile, the terminal is in one of an RRC idle or RRC connected state, and the V2X direct communication resource used by the terminal is a V2X direct communication resource allocated by the base station through an explicit resource request processing process. The terminal may be a randomly selected V2X direct communication resource or a preset V2X direct communication resource.

20 is a diagram for explaining one embodiment of local transmission according to the embodiment of the second disclosure.

In step 511-1 or step 511-2, the terminal 1 101 transmits a V2X message requiring local transmission to the base station 107 or the terminal 2 102 using the allocated V2X direct communication resource according to the above-described method. . The terminal 2 102 receives the V2X message from the V2X direct communication resource, and the base station 107 monitors the V2X message from the V2X direct communication resource according to the instruction of the terminal 1 101. The base station 107 may receive a V2X message transmitted on a V2X direct communication resource during the cellular communication period. During the cellular communication period, the base station 107 monitors packets from terminals as well as packets between terminals using V2X direct communication. When the base station 107 receives the V2X message including the local transmission indicator, the base station 107 forwards the V2X message to the

terminals

103, 104, and 105 within the corresponding coverage (513-3 to 513-5).

As described above, the terminal 1 101 may transmit a local transmission indicator to the base station 107 using the V2X direct communication resource request. Here, the V2X direct communication resource is for V2X message transmission requesting local transmission. Alternatively, terminal 1 101 may transmit a local transmission indicator to base station 107 via a cellular communication resource request. Wherein the cellular communication resource is for V2X message transmission requesting local transmission. Alternatively, the terminal 1 101 may transmit a V2X message to the base station 107 requesting local transmission through a cellular communication scheme. The format of the V2X message transmitted from the terminal 1 101 to the base station 107 may be a control plane signaling message such as an RRC message.

Meanwhile, when the base station 107 receives a V2X message requesting local transmission, the base station 107 transmits the V2X message through the V2X channel established between the base station 107 and the V2X capable terminals. As another example, an MBMS or eMBMS channel for V2X may be used. As another example, a DL shared channel (DL SCH) for V2X may be used. On the other hand, V2X RNTI or V2X local RNTI may be used to identify the resource containing the V2X message. For reference, the format of the V2X message transmitted by the base station 107 may be one of an RRC, MAC, PDCP, or application layer based message. The format of the V2X message will be described later.

21 is a diagram for explaining another embodiment of local transmission according to the embodiment of the second disclosure.

Compared to FIG. 20, there is a difference in that the RSU 110 is used in the embodiment of FIG. 21. When the RSU 110 or the terminal has relay capability for another RSU 110 or another terminal that is outside the coverage of the base station 107, the relay-enabled RSU 110 or the relayable terminal is the other RSU 110. Or V2X messages from other terminals to the base station 107. In FIG. 21, the terminal 1 101 is outside the coverage of the base station 107, and the RSU 110, the terminal 2 102, the terminal 3 103, the terminal 4 104, and the terminal 5 105 are the base station ( Assume that it is within the coverage of 107). The RSU 110 capable of relaying may inform its relay capability through a V2X message, for example, a V2X application code indicating a relay device.

Referring to FIG. 21, if UE 1 101 determines that a V2X message requires local transmission, UE 1 101 searches for another UE or RSU 110 capable of providing a connection with BS 107. . In FIG. 21, it is assumed that the terminal 1 101 receives a V2X message from the RSU 110 indicating the relay capability. In step 602, the terminal 1 101 that detects an entity having a relay capability transmits a V2X message to the RSU 110. The V2X message includes a local transmission indicator. The local transmission indicator may be transmitted to the RSU 110 via a resource previously allocated for the V2X message. In step 603, the RSU 110 transmits a V2X message including the local transmission indicator to the base station 107. In step 604, the base station 107 transmits the received V2X message to the terminal 2 102, the terminal 3 103, the terminal 4 104, and the terminal 5 105 located within its own coverage. For reference, the RSU 110 and the base station 107 may communicate in a cellular communication scheme. Alternatively, the interface between the RSU 110 and the base station 107 may be a non-3GPP interface.

As illustrated in FIG. 20, when the base station receives a V2X message requesting local transmission, the base station transmits the V2X message through a V2X channel established between the base station and the V2X capable terminals. As another example, an MBMS or eMBMS channel for V2X may be used. As another example, a DL shared channel (DL SCH) for V2X may be used. On the other hand, V2X RNTI or V2X local RNTI may be used to identify the resource containing the V2X message. For reference, the format of the V2X message transmitted by the base station may be one of an RRC, MAC, PDCP, or application layer based message.

An example of V2X code for emergency service is shown in Table 1 below.

As in the example of Table 1, the information of the V2X code for the emergency service may be embedded in the SIM of the terminal, or may be received from the server or the base station managing the V2X code when the terminal registers the V2X service. The V2X terminal stores the V2X code and the V2X event mapping table as shown in Table 1 above. On the other hand, the V2X code for the non-emergency service is a code value other than the V2X code for the emergency service.

Hereinafter, a code or a carrier used according to the type of a V2X service will be described.

Meanwhile, depending on the type of V2X service, a code or carrier for transmitting a V2X message for each V2X service requiring a low delay and a typical V2X service may vary. The low latency V2X service may be, for example, an emergency message service, and a typical V2X service may be, for example, a service providing general information such as informing a driver of a parking lot in an adjacent area. Can be.

22A to 22C illustrate codes used for transmitting a V2X message according to a delay time required for transmitting a V2X message according to an embodiment of the second disclosure.

FIG. 22A illustrates operations according to a terminal 101-1 that is a vehicle using an emergency V2X service and a terminal 101-2 that is a vehicle using a non-emergency V2X service.

First, the terminal 101-1 using the emergency service will be described. Based on the emergency service code table of Table 1, the emergency service terminal 101-1 transmits V3X code 3 corresponding to “emergency vehicle warning” to other vehicles (terminals). . Upon receiving the V3X code 3 corresponding to the "emergency vehicle warning", the terminal 2 102 can recognize the emergency service event corresponding to the V3X code 3 from the pre-stored emergency service event table. Thereafter, an operation corresponding to the emergency service event, for example, a warning sound may be generated to the driver.

Next, assuming that a non-emergency service, for example, a parking spot notification service is provided by the RSU 110, the RSU 110 sends a "remaining parking spot" to the terminal 101-2. Transmit a V2X code corresponding to " The terminal 101-1 receiving the V2X code corresponding to the "remaining parking spot" does not know the code for the non-emergency service. Accordingly, the terminal 101-1 inquires the V2X server 109 received by the V2X server 109 via the base station 107 or the base station 107 in step 701, and the base station 107 or the V2X server 109. Information about the remaining parking spot.

22B illustrates the message flow in an emergency V2X service.

In operation 711, the terminal 1 101 determines the emergency situation A. The occurrence of the emergency situation A may be determined using various sensors and cameras attached to the vehicle, or may be based on information received from the RSU 110 / base station 107 / server 109. In step 713, the V2X code corresponding to the emergency situation A is selected and transmitted to the neighboring terminal, that is, the terminal 2 (102). A resource for transmitting the V2X code may be selected from a preconfigured resource set. Terminal 2 (102) can know the emergency situation corresponding to the received V2X code using the mapping table of Table 1 it has. The terminal 2 102 selects a resource for receiving the V2X code from a preconfigured resource set. Although the base station 107 and the server 109 are shown in (b), it can be seen that they are not involved in emergency services. (V2X code recipient and source resource set may be different or the same)

FIG. 22C illustrates the message flow in a non-emergency V2X service.

In step 721, the terminal 1 101 transmits a V2X code corresponding to the non-emergency service to the terminal 2 102. The resource for transmitting the V2X code may be selected from a preconfigured resource set. In step 723, the terminal 2 102 selects a resource for receiving the V2X code from a preconfigured resource set, and searches for a V2X code received through the corresponding resource in the table of Table 1. The received code is for a non-emergency service and will not be retrieved from the table in Table 1. Accordingly, the terminal 2 102 transmits the V2X code via the base station 107. In operation 725, the server 109 transmits service information corresponding to the corresponding V2X code to the terminal 2 102 via the base station 107. In operation 727, the terminal 2 102 may know information of a service corresponding to the received V2X code, for example, a parking notification service, and provide parking information to the driver.

FIG. 23 is a diagram illustrating that carriers used for transmission of a V2X message are classified according to a delay time required for transmission of a V2X message according to an embodiment of the second disclosure.

In FIGS. 22A to 22C, emergency service V2X codes and non-emergency service V2X codes are distinguished. In FIG. 23, a carrier for transmitting an emergency service V2X code and a carrier for transmitting an emergency service V2X code may be distinguished and operated.

(a) indicates that an emergency service carrier is used for transmission of an emergency service V2X code. Terminal 1 (101) detects an unauthorized crossing of the pedestrian and transmits an emergency V2X code corresponding to the pedestrian attention notification through the carrier for emergency V2X transmission. Terminal 2 (102) may monitor the emergency V2X code transmission carrier to receive the emergency V2X code. Meanwhile, the terminal 2 102 may search for the received V2X code in the V2X code and the V2X event mapping table to know the V2X event corresponding to the V2X code. Thereafter, the terminal 2 102 may generate an operation corresponding to the V2X event, for example, a pedestrian warning notification alert.

(b) indicates that a non-emergency service carrier is used for transmission of a non-emergency service V2X code.

Referring to (b), the terminal 3 103 receives the V2X code X through the non-emergency V2X code transmission carrier while monitoring the emergency V2X code transmission carrier and the non-emergency V2X code transmission carrier. Terminal 3 (103) retrieves the received V2X code from the V2X code and the V2X event mapping table. Since the V2X code is a non-emergency code, the received V2X code is not included in the mapping table. Accordingly, the terminal 3 103 transmits the V2X code X to the V2X server 109 via the base station 107 or the base station 107. The V2X server 109 transmits the V2X content corresponding to the V2X code to the terminal 3 (103). The V2X content may be, for example, traffic flow information. The vehicle terminal 3 (103) having obtained the V2X content notifies the driver of the V2X content.

Although (a) and (b) described an embodiment of transmitting a V2X code, an embodiment in which a V2X message is transmitted and received through an emergency V2X transmission carrier or a non-emergency V2X transmission carrier is also included. In addition, (b) has been described an example in which the terminal 3 (103) receiving the non-emergency V2X code to obtain the V2X content through the V2X server 109, the base station 107 includes the function of the V2X server 109 Thus, a local forwarding scheme for obtaining V2X content from the base station 107 is also possible.

Meanwhile, in (a) and (b), terminal 1 (101), terminal 2 (102), and terminal 3 (103) monitor the emergency V2X transmission carrier and the non-emergency V2X transmission carrier. Assuming that the period in which the terminals monitor the emergency V2X transmission carrier is set to "a", and the period in which the terminals monitor the non-emergency V2X transmission carrier can be set to "b", the value of a is not greater than b. . That is, the period for monitoring the emergency V2X transmit carrier is shorter than or equal to the period for monitoring the non-emergency V2X transmit carrier. This is because monitoring for emergency events needs to be done more frequently than monitoring for non-emergency events.

24 is a diagram illustrating message transmission and reception for an emergency service and a non-emergency service according to an embodiment of the second disclosure.

As described above, in FIG. 24, the terminal 1 101, the terminal 2 102, and the terminal 3 103 each monitor the emergency V2X transmission carrier at a period a and monitor the non-emergency V2X transmission carrier at a period b. In addition, a <b or a = b.

Steps 913 to 915 describe the message transmission and reception process for the emergency service according to FIG. 23 (a).

In step 911, the terminal 1 101 determines the detected emergency situation A. In step 913, the terminal 1 101 selects a V2X code transmission resource from a preset resource set and broadcasts a V2X code corresponding to the emergency A through the selected resource. The terminal 2 102 receives the V2X code through a preset resource set selected resource. The terminal 2 102 may search for the received V2X code in the mapping table for the V2X code and the V2X event and may know the emergency situation A corresponding to the V2X code.

Steps 917 to 923 describe a message transmission / reception process for the non-emergency service according to FIG. 23 (b).

In step 917, the terminal 3 103 determines the V2X service B. In addition, it is assumed that the service B is an emergency service such as traffic flow information or parking lot information. Terminal 3 (103) selects a V2X code transmission resource from a preconfigured set of code resources to transmit the information for the V2X service B and broadcasts the V2X code. The V2X code for the service B transmitted by the terminal 3 103 is received from another vehicle terminal (eg, the terminal 2 102) from the V2X code receiving resource. In step 919, the terminal 2 102 receives the V2X code. The V2X code retrieves the received V2X code from the mapping table for the V2X code and the V2X event, since the received V2X code is a code for non-emergency service, the V2X code will not be included in the mapping table. ) Transmits the V2X code to the V2X server 109 via the base station 107. However, if the base station 107 includes the function of the V2X server 109, the V2X code is transmitted to the base station 107. The V2X server 109 or the base station 107 that has received the V2X code in step 921 transmits V2X content information corresponding to the V2X code to the terminal 2 102. In step 923, the terminal 2 102 ) V2X corresponding to the V2X content The service B may be known to perform an operation corresponding to the V2X service B. For example, a notification signal for the V2X service B is generated to the driver.

On the other hand, in the description of the embodiments it is assumed that the resources for the transmission / reception of the V2X code is pre-configured, the resources for the transmission and reception of the V2X code may be operated in other ways. Hereinafter, an operation method for resources for transmitting and receiving V2X code will be described.

It is assumed that the V2X code is divided into emergency and non-emergency services.

Transmit resources for emergency services V2X codes and for non-emergency services V2X codes can be differentiated and operated by service requirements (QoS) (e.g., time delay, reliability) and are required to meet service requirements. The number of retransmissions, resource allocation interval, and amount of resources are determined.

In addition, the probability of resource usage (or weight of resource usage) used to transmit an emergency V2X message may be managed differently for each type of emergency service. That is, when the terminal for transmitting the emergency service code 1 and the terminal for transmitting the emergency service code 2 compete for resources at the same time, the terminal may use a higher resource use probability for the emergency service code 1 to operate. have. For example, if the probability of using the transmission resource of the emergency service code 1 is set to 1 and the probability of using the transmission resource of the emergency service code 2 is set to 0.93, the terminal 1 and the emergency service code 2 to transmit the emergency service code 1 are set. The terminal 2 to be transmitted decides to use the corresponding resource with a probability of 1 and 0.93, respectively, for the same transmission resource.

Meanwhile, the transmission / reception resource set of the V2X code may be reconfigured based on the number of terminals to use the transmission / reception resources of the V2X code or service content generated in a specific region, and the situation or emergency situation of the corresponding region for triggering the reconfiguration of the resource set. The information may be reported to the base station by the RSU or the terminal.

An example of using the V2X code resource is shown below.

(1) Use pre-configured resources for emergency service V2X code, and use resources for direct communication between terminals in general for non-emergency service V2X code.

(2) Use resource A preconfigured for the V2X code for emergency services, and use resource B preconfigured for the V2X code for non-emergency services.

(3) Use resource C for emergency service V2X code and resource D for non-emergency service V2X code.

(4) V2X code for emergency services and V2X code for non-emergency services use preconfigured resource X.

(5) V2X codes for emergency services and V2X codes for non-emergency services use resource Y. (Temporarily allocated resource Y)

On the other hand, the resources for the transmission of the V2X code is allocated to the terminal through a unicast message between the base station and the terminal, the broadcast message transmitted by the base station, or configured in advance in the terminal does not require signaling for the separate resource allocation to the terminal Can be.

Meanwhile, the operation example of the transmission resource of the V2X code described above may be applied to the operation of the transmission / reception resource for the V2X message.

In addition, the emergency service code and the non-emergency service code may include the information of Table 2 below.

Hereinafter, examples of MAC layer signaling for supporting a V2X service will be described.

FIG. 25 illustrates an example of MAC layer signaling for V2X service support according to an embodiment of the second disclosure.

The message format of the V2X service may be composed of a MAC PDU, a header, and a subheader.

(a) is an example of transmitting a V2X service message using a sidelink resource 1001 which is a D2D system of 3GPP LTE. SCI format 0 (1008) includes transmission resource information of a V2X service message. That is, the SCI format 1008 indicates information such as resources (frequency, time, etc.), MCS, period, etc. for V2X service message transmission. The V2X service message is exchanged between the terminal 1 (101) and the terminal 2 (102) using the resource indicated by the SCI format (1008).

(b) shows a V2X signal structure composed of MAC layer signals proposed in the second disclosure.

Meanwhile, an example of the V2X discovery signal includes the fields of Table 3 below.

Another example of the V2X search signal includes the fields of Table 4 below.

Another example of the V2X search signal includes the fields of Table 5 below.

For reference, the MAC layer discovery packet may be implemented as a MAC layer header or a MAC layer subheader of the V2X communication system. For reference, other information required for the V2X discovery operation may be, for example, PLMN information and APN information, and may be included in the payload portion of the MAC layer discovery packet and transmitted.

Meanwhile, a Scheduling Assignment (SA) indicating a resource to which the MAC layer signal is transmitted, that is, an SCI format may be masked with an identifier indicating that it is a V2X service. In another embodiment, the SA may be masked as an emergency V2X service indicator or a non-emergency V2X service indicator. In another embodiment, the SA may be masked as an indicator indicating a specific emergency V2X service, and it is assumed that the specific emergency V2X service and a masking value corresponding thereto are predefined.

In addition, the 1-bit indicator of the SCI format 0 (or other types of SCI format may be used) may be used as a non-emergency V2X service indicator / emergency V2X service indicator.

Meanwhile, for the MAC layer signaling configured as described above, the transmission resource for the MAC layer signal may be operated as in the following example.

Based on the requirements of the emergency V2X service, the class of the transmission resource may be defined in advance, and the MAC layer signal of the emergency service may be transmitted through the resource of the predetermined class. Meanwhile, the number of retransmissions, resource allocation period, and resource allocation amount are predetermined by the transmission resource class.

-The transmission resource for V2X service is operated separately.

-Separate resources for V2X emergency service and resources for V2X non-emergency service.

Hereinafter, a message flow for an embodiment of masking and transmitting an SA according to the above description will be described.

FIG. 26 is a diagram illustrating a message flow when a V2X message is transmitted after masking an SA with an emergency V2X code according to an embodiment of the second disclosure.

In operation 1101, the terminal 1 101 determines the emergency situation A.

In step 1103, the terminal 1 101 configures an emergency V2X message for the emergency A, selects a resource to transmit the emergency V2X message from a preconfigured resource set, and transmits information about the emergency V2X message through the selected resource. Configure and transmit SA including. Meanwhile, the SA is masked with a code indicating that it is an emergency V2X message. For reference, the terminal 2 102 selects a resource for receiving the SA from a preconfigured resource set and receives the SA transmitted by the terminal 1 101.

In step 1105, the terminal 1 101 transmits a V2X message through the corresponding resource according to the resource information indicated by the SA. For reference, the terminal 2 102 may know a transmission resource of the V2X message transmitted by the terminal 1 101 based on the information indicated by the SA received in step 1103, and receive the V2X message from the corresponding transmission resource. can do. Meanwhile, the V2X message includes content for emergency situation A. Accordingly, in operation 1107, the terminal 2 102 may know the emergency A and perform an operation corresponding to the emergency A. FIG.

Note that in FIG. 26, the base station and the V2X server are not necessary for the operation between the terminals. That is, since the SA is made only between the terminals, and the V2X message is a message for an emergency situation, the base station and the V2X server are not necessary.

FIG. 27 is a diagram illustrating a message flow when transmitting a V2X code after masking an SA with an emergency V2X code according to an embodiment of the second disclosure.

In FIG. 26, after UE 1 101 masks and transmits an SA with an emergency V2X code in step 1103, UE 1 101 transmits a V2X message in step 1105. On the other hand, in FIG. 27, after UE 1 101 masks and transmits an SA with an emergency V2X code in step 1203, UE 1 101 transmits a message including an emergency V2X indicator and contents for emergency situation A in step 1205. The difference is that it transmits. Since other descriptions are the same as in FIG. 26, duplicated descriptions are omitted.

As another embodiment of FIG. 27, in step 1203, the SA is masked with the emergency V2X code, but may be masked with a general D2D indicator instead of the emergency V2X code. In another embodiment, in step 1203, the terminal 1 101 configures an emergency V2X message for emergency A, configures an SA including transmission information on the configured emergency V2X message, and indicates that the SA is an emergency V2X message. The notification can also be masked with an indicator.

That is, according to the embodiment of Figs. 26 and 27, the SA is masked with an emergency V2X code (step 1103), masked with a general D2D code (modification embodiment), or notified of an emergency V2X message. It can be masked with an indicator (variant embodiment). In addition, after the SA is masked and transmitted, a V2X message may be transmitted (step 1105), or a message including an emergency V2X indicator and contents of emergency situation A (step 1205) may be transmitted.

Hereinafter, description will be made of a search signal for performing communication between V2X devices located outside the coverage of the cellular base station in the V2X communication system.

FIG. 28 is a diagram illustrating an example of communication between V2X devices outside coverage of a cellular base station in a V2X communication system according to an embodiment of the second disclosure.

Referring to (a), in the V2X communication system, direct communication between V2X devices within the coverage of the cellular base station and direct communication between V2X devices outside the coverage 1301 of the cellular base station are possible. That is, in (a), direct communication between the terminal 1 (101), the terminal 2 (102), and the terminal 3 (103) is possible. In order to perform direct communication between V2X devices outside the coverage 1301 of the cellular base station, a scheme is required for the UEs to discover each other.

Referring to (b), in the V2X communication system, the terminal 1 (101), which is a V2X device in the coverage 1302 of the cellular base station, is a relay device, and the terminal 1 (which is a V2X device outside the coverage 1302 of the cellular base station). 101, the terminal 2 102 or the terminal 3 103 and the base station 110 may perform communication.

29 is a diagram illustrating a protocol layer for processing discovery signals in a V2X communication system according to an embodiment of the second disclosure.

Examples of protocol stacks for processing V2X discovery signals proposed in the second disclosure are shown in (a), (b), (c).

(a) is a protocol stack when a V2X discovery signal is transmitted on a V2X physical channel and processed at the PDCP layer. Receiving discovery information transmitted from the V2X protocol layer, the PDCP layer generates a PDCP layer packet including information indicating that the discovery information is a V2X discovery and delivers it to a lower layer. In addition, the PDCP layer restores the packet received from the lower layer to the PDCP layer packet, checks the information indicating the V2X discovery, and delivers the discovery information to the protocol layer. (a) is also the protocol stack when the V2X discovery signal is processed in the V2X protocol layer. The V2X protocol layer generates a packet including information indicating that it is a V2X discovery and delivers it to a lower layer or restores the packet to a V2X protocol layer packet from a packet received from a lower layer, and then confirms the information indicating that it is a V2X discovery.

(b) is a protocol stack when a V2X discovery signal is transmitted over a V2X communication physical channel and processed at the MAC layer. When the MAC layer receives the packet received from the upper layer, and confirms that the received packet is a packet for V2X discovery, the MAC layer generates a MAC layer packet including the V2X discovery indication information and delivers it to the lower layer. The MAC layer restores the MAC layer packet from the packet received from the lower layer, and then checks information indicating V2X discovery.

(c) is a protocol stack when a V2X discovery signal is transmitted over a V2X discovery physical channel and processed at the physical (PHY) layer. If the packet transmitted from the V2X protocol includes V2X discovery information, the PHY layer inserts and transmits a code corresponding to the V2X discovery into a PHY layer resource. The code corresponding to the V2X discovery transmitted by the PHY layer is transferred to the V2X protocol layer and used to confirm the V2X discovery information. The V2X discovery code may use the same value worldwide, use the same value for each PLMN, use the same value for each APN, or define and use a value only for a specific service.

30 is a diagram illustrating an example of searching for a relay device in a V2X communication system according to an embodiment of the second disclosure.

In step 1511, the V2X protocol 1502 of the relay device transmits V2X relay discovery information to the relay device 1501 (particularly, to the L2 layer) indicating that the relay device is in the vicinity. For reference, the V2X protocol 1502 of the relay device may be implemented in a separate entity, such as a server, or may be implemented in the relay device 1501. The V2X relay discovery information includes at least one of an relay device identifier (Application ID), a group identifier, a PLMN identifier, and APN information.

The relay device 1501 (particularly, the L2 layer) processes the relay device information received from the V2X protocol 1502 of the relay device to generate V2X relay discovery information. The V2X relay discovery information is an L2 message. In step 1513, the relay device 1501 selects a transmission resource for transmitting the L2 message, and transmits the V2X relay discovery information to the remote device 1503 in step 1515. For reference, the L2 message includes V2X relay discovery indication information generated in the PDCP layer or V2X relay discovery indication information generated in the MAC layer. Alternatively, a Scheduling Assignment (SA) for transmitting the L2 message is masked and transmitted using the V2X relay discovery indication information.

Upon receiving the V2X relay discovery signal, the remote device 1503 (particularly, the L2 layer) transmits the relay device information to the V2X protocol 1504 of the remote device in step 1517. For reference, the V2X protocol 1504 of the remote device may be configured in a separate entity, but considering that the remote device 1503 is a normal terminal device, the V2X protocol 1504 of the remote device is the remote device 1503. Is usually implemented inside the.

In step 1519, the V2X protocol 1504 of the remote device verifies the relay device information. If the information on the relay device detected from the V2X relay discovery information is not sufficient, the remote device 1503 may request a relay request (Relay), which is a signal for requesting additional information related to relay, to the relay device 1501 in step 1519. -Request).

In step 1523, the relay device 1501 transmits a relay confirm message in response to the relay request. The relay confirmation message includes additional information necessary for the remote device 1503 and the relay device to perform relay communication. Information further exchanged through the relay request message and the relay confirmation message may include, for example, a PLMN identifier or an APN Info.

Based on the above description, a case in which the V2X relay discovery information (L2 message) transmitted by the relay device 1501 corresponds to a MAC layer L2 message will be described below.

The V2X relay discovery information includes at least one information such as a relay device indicator, a relay device identifier, a group identifier supported by the relay device, a PLMN identifier, and APN information. The remote device 1503 receives the V2X relay discovery information and selects the relay device 1501 and sends it to the relay device 1501 to initiate an operation of establishing a connection to the network through the relay device 1501. Send a relay request message. The relay request message may be transmitted even if additional information is required for the remote device 1503 to select the relay device 1501. The relay device 1501 receiving the relay request message transmits a relay acknowledgment message in response thereto, and the relay acknowledgment message may include information necessary to provide connectivity between the remote device 1503 and a network. .

FIG. 31 is a diagram for describing a process of a remote device searching for a neighboring relay device according to an embodiment of the second disclosure.

In step 1611, the V2X protocol 1504 of the remote device generates and transmits V2X relay request information to the remote device 1503 in order to search for a neighboring relay device 1501 in order to secure connectivity to the network. The V2X relay request information includes at least one of a UE identifier, a group identifier, a relay device discovery indicator, a PLMN identifier, and APN information. Accordingly, the remote device 1503 (particularly, the L2 layer) processes the relay device discovery information received by the V2X protocol to generate V2X relay request information, which is an L2 message. In step 1613, the remote device 1503 selects a transmission resource for transmitting the L2 message (ie, V2X relay request information), and transmits the L2 message in step 1615. The L2 message may include V2X relay request indication information generated in the PDCP layer or V2X relay request indication information generated in the MAC layer. Meanwhile, the remote device 1503 may mask and transmit a resource allocation indicator (SA) to transmit the L2 message with the V2X relay request indication information. Upon receiving the V2X relay request message, the relay device 1501 (in particular, the L2 layer) transmits relay device discovery information of the remote device 1503 to the V2X protocol 1502 of the relay device in step 1617. In step 1619, the V2X protocol 1502 of the relay device checks the relay device discovery information, constructs relay device information indicating that the relay device is a relay device, and transmits the relay device information to the remote device 1503 (particularly, an L2 layer). The relay device information includes at least one of a relay device identifier, a group identifier, a PLMN identifier, and APN information. Meanwhile, the relay device 1501 (particularly, the L2 layer) processes the relay device information received by the V2X protocol 1502 of the relay device to generate V2X relay discovery information (L2 message). Thereafter, the relay device 1501 selects a transmission resource for transmitting the L2 message, and then transmits the L2 message in step 1621.

The L2 message (ie, V2X relay discovery information) includes V2X relay discovery indication information generated at the PDCP layer or V2X relay discovery indication information generated at the MAC layer. In addition, the relay device 1501 masks and transmits a Scheduling Assignment (SA) to transmit the L2 message with the V2X relay discovery indication information.

Upon receiving the V2X relay discovery information, the remote device 1503 (particularly, the L2 layer) transmits the relay device information to the V2X protocol 1504 of the remote device in step 1623. In step 1625, the V2X protocol 1504 of the remote device checks the relay device information and transmits the relay device information to the remote device 1503. Thereafter, in step 1627, the remote device 1503 relays a relay request message to select the relay device 1501 based on the relay device information and to start an operation of establishing a connection to the network through the relay device 1501. Transmit to device 1501. The relay request message may be transmitted even if additional information is required for the remote device 1503 to select the relay device 1501.

The relay device 1501 receiving the relay request signal transmits a relay acknowledgment message in response to the relay request signal in step 1629. The relay confirmation message may include information necessary to provide connectivity between the remote device 1503 and a network. For example, the relay confirmation message may include information not included in the V2X discovery L2 message, such as PLMN identifier or APN information.

32 is a diagram for explaining another example of searching for a relay device in a V2X communication system according to an embodiment of the second disclosure.

The procedure of FIG. 32 is the same in procedure as described in FIG. In FIG. 30, the V2X relay discovery information is processed in the L2 layer, whereas in FIG. 32, the V2X relay discovery ID is processed in the physical channel. That is, FIG. 30 is an example based on an L2 message, and FIG. 32 is a difference based on an L1 message. In FIG. 32, the V2X relay discovery ID includes a relay device indicator, and the V2X relay discovery ID may be configured to use the same value worldwide, the same value for each PLMN, or the same value for each APN.

In detail, in step 1711, the V2X protocol 1502 of the relay device configures a V2X relay discovery ID for notifying the peripheral device that the relay device is a relay device, and transmits the V2X protocol to the relay device 1501. A resource for transmitting the V2X relay discovery ID including the V2X relay discovery information is selected and transmitted to the remote device 1503 through the PHY channel in step 1715. The V2X relay discovery ID including the relay device indicator may be set to use the same value worldwide, the same value for each PLMN, or the same value for each APN.

The remote device 1503 that has received the V2X relay discovery ID in step 1717 transmits the received V2X relay discovery ID to the V2X protocol 1504 of the remote device, and in step 1719 the V2X protocol 1504 of the remote device transmits the V2X. The relay device indicator is identified and obtained from the relay discovery ID, and the relay device indicator is transmitted to the remote device 1503. In step 1721, the remote device 1503 transmits a relay request message to the relay device in order to obtain the relay device 1501 that has transmitted the V2X relay discovery ID and detailed information necessary for network connection. The relay request message includes PHY channel information on which the V2X relay discovery ID is transmitted. In addition, the relay request signal may include an identifier, a group identifier, a PLMN identifier, and APN Info of the remote device 1503. The relay device 1501 receiving the relay request signal determines whether the relay device 1501 is a target relay device based on the included PHY channel information. In step 1723, the relay device 1501 transmits a relay acknowledgment message including at least one of a relay device identifier, a group identifier, a PLMN identifier, APN Info, and PHY channel information transmitted from the V2X relay discovery ID.

33 is a diagram for describing a process of a remote device searching for a neighboring relay device according to an embodiment of the second disclosure.

33 is identical in procedure to that described in FIG. In FIG. 31, the V2X relay request information is processed in the L2 layer. However, in FIG. 33, the V2X relay request ID is processed in the physical channel. That is, FIG. 32 is an example based on an L2 message, and FIG. 33 is different from an example based on an L1 message. In FIG. 33, the V2X relay request ID includes a relay device indicator, and the V2X relay request ID is the same value worldwide.

In detail, in operation 1801, the V2X protocol 1504 of the remote device constructs a V2X relay request ID (relay device search indicator) and transmits the same to the remote device 1503 in order to search for a neighboring relay device. In operation 1803, the remote device 1503 selects a PHY channel resource from among preconfigured resource sets and transmits a V2X relay request ID including a relay device discovery indicator to the relay device.

The relay device 1501 receiving the V2X relay request ID in step 1807 transfers it to the V2X protocol 1502 of the relay device, and in step 1809, the V2X protocol 1502 of the relay device indicates that it is a relay device. The relay discovery information is configured and delivered to the relay device 1501. The V2X relay discovery information is a relay device indicator (Application ID). In step 1811, the relay device 1501 selects a resource for transmitting the V2X relay discovery ID including the V2X relay discovery information and transmits the resource to the remote device 1503 using the PHY channel. The V2X relay discovery ID including the relay device indicator is set to use the same value globally, use the same value for each PLMN, or use the same value for each APN.

The remote device 1503 that has received the V2X relay discovery ID transmits the received V2X relay discovery ID to the V2X protocol 1504 of the remote device in step 1813, and the V2X protocol 1504 of the remote device indicates relay device indicator information. Obtain by checking. Thereafter, in step 1817, the remote device 1503 transmits a relay request message to the relay device 1501 to obtain the relay device 1501 that has transmitted the V2X relay discovery ID and detailed information necessary for network connection. The relay request signal includes PHY channel information on which the V2X relay discovery ID is transmitted. In addition, the relay request signal may include an identifier, a group identifier, a PLMN identifier, and APN Info of the remote device 1503. In operation 1819, the relay device 1501 receiving the relay request signal determines whether the relay device 1501 is a target relay device based on the PHY channel information, and the relay device 1501 may include a relay device identifier, a group identifier, a PLMN identifier, A relay acknowledgment message including at least one of APN Info and PHY channel information transmitting the V2X relay discovery ID is transmitted to the remote device 1503.

Hereinafter, configurations of a terminal device and a base station device operating according to the embodiments of the second disclosure will be described.

34 is a diagram illustrating a configuration of a terminal device according to embodiments of the second disclosure.

The transceiver 1901 performs signal transmission and reception with external entities, that is, a base station, another terminal, an RSU, and the like. To this end, the transmission and reception unit may be composed of an RF transmitter for up-converting and amplifying the frequency of the transmitted signal, and an RF receiver for low noise amplifying and down-converting the received signal. The transmitter / receiver may receive a signal through a wireless channel, output the signal to the controller 1903, and transmit a signal output from the controller 1903 through the wireless channel. In addition, the transceiver 1901 may include a communication module for supporting various communication schemes such as cellular communication and direct communication between terminals.

The controller 1903 controls the overall operation according to the above-described embodiments of the second disclosure. For example, by determining an emergency situation, it is determined whether V2X message for informing the emergency situation is to perform direct communication between terminals or local transmission through a base station. In addition, various types of messages required as described above are generated. In addition, the V2X message received from another terminal is analyzed to relay the message or perform an operation corresponding to the message. Meanwhile, the terminal device may be an entity having a relay function such as an RSU. Accordingly, the controller 1903 may perform a relay operation.

The storage unit 1905 stores information necessary in embodiments of the second disclosure. The necessary information includes, for example, a mapping table between V2X application code and V2X information.

35 is a diagram illustrating a configuration of a base station apparatus according to embodiments of the second disclosure.

The transceiver 2001 performs signal transmission / reception with external entities, that is, a terminal, an RSU, and the like. To this end, the transmission and reception unit may be composed of an RF transmitter for up-converting and amplifying the frequency of the transmitted signal, and an RF receiver for low noise amplifying and down-converting the received signal. In addition, the transceiver may receive a signal through a wireless channel, output the signal to the controller 2003, and transmit a signal output from the controller 2003 through the wireless channel.

The controller 2003 controls the overall operation according to the above-described embodiments of the second disclosure. For example, it is determined whether the V2X message received from the terminal or the RSU includes the local transmission indicator, and if the local transmission indicator is included, the V2X message is transmitted to the terminals within the cell coverage. In addition to the above example, all operations of the base station are controlled. However, since this has been described herein, a detailed description thereof will be omitted.

The storage unit 2005 stores information necessary in the embodiments of the second disclosure.

Certain aspects of the present disclosure described above may also be embodied as computer readable code on a computer readable recording medium. A computer readable recording medium is any data storage device capable of storing data that can be read by a computer system. Examples of the computer readable recording medium include read-only memory (ROM), random-access memory (RAM), CD-ROMs, magnetic tapes, Floppy disks, optical data storage devices, and carrier waves (such as data transmission over the Internet). The computer readable recording medium can also be distributed through network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion. In addition, functional programs, code, and code segments for achieving the present disclosure may be readily interpreted by those skilled in the art to which the present disclosure applies.

In addition, it will be appreciated that an apparatus and method according to one embodiment of the present disclosure may be realized in the form of hardware, software or a combination of hardware and software. Any such software may be, for example, volatile or nonvolatile storage, such as a storage device such as a ROM, whether or not removable or rewritable, or a memory such as, for example, a RAM, a memory chip, a device or an integrated circuit. Or, for example, CD or DVD, magnetic disk or magnetic tape and the like can be stored in a storage medium that is optically or magnetically recordable and simultaneously readable by a machine (eg computer). The method according to an embodiment of the present disclosure may be implemented by a computer or a portable terminal including a control unit and a memory, wherein the memory is suitable for storing a program or programs including instructions for implementing the embodiments of the present disclosure. It will be appreciated that this is an example of a machine-readable storage medium.

Thus, the present disclosure includes a program comprising code for implementing the apparatus or method described in any claim herein and a machine-readable storage medium storing such a program. In addition, such a program may be transferred electronically through any medium, such as a communication signal transmitted via a wired or wireless connection, and the present disclosure suitably includes equivalents thereof.

In addition, a device according to an embodiment of the present disclosure may receive and store the program from a program providing device connected by wire or wirelessly. The program providing apparatus includes a memory for storing a program including instructions for causing the program processing apparatus to perform a preset content protection method, information necessary for the content protection method, and wired or wireless communication with the graphic processing apparatus. A communication unit for performing, and a control unit for automatically transmitting a request or a corresponding program to the transceiver device.

Claims

In a search method for communication between devices,

Generating a discovery signal including discovery information;

Selecting a transmission resource to transmit the discovery signal;

Transmitting the discovery signal through the selected transmission resource;

And when a request signal for requesting additional information related to search is received from the counterpart device receiving the search signal, transmitting a confirmation signal including the requested additional information to the counterpart device. .
The method of claim 1, wherein the search signal,

Masking with a PDCP packet including a relay device search indicator related to the relay device transmitting the discovery signal, a MAC packet including the relay device search indicator, a physical layer packet including the relay device search identifier, and the relay device search indicator At least one of the allocated resource allocation indicators,

The MAC packet includes a version field, a reserved field, a source field, and a destination field, wherein the version field is used to indicate repeater search or group member search, or a value of the reserved field is changed. It is used to instruct to search for repeater or group member.

And the source field includes one of a relay device identifier, a group identifier, and an application identifier, and the destination field includes an identifier of a device or a group to receive the discovery signal.
The method of claim 1, wherein the search signal,

A PDCP packet including a search indicator indicating a search for service provision by a device transmitting the search signal, a MAC packet including the search indicator, a physical layer packet including the search indicator, and masked with the search indicator And at least one of a resource allocation indicator and a discovery message configured in a service layer signaling format.
The method of claim 1, wherein the search signal,

And an identifier indicating service information or group information provided by the device transmitting the discovery signal.
The method of claim 1, wherein the search information,

And at least one of a relay device identifier, a group identifier, a public land mobile network (PLMN) identifier, access point name (APN) information, and an application identifier associated with the relay device sending the discovery signal.
The method of claim 1, wherein the search information,

And at least one of a group identifier, a service identifier, and a device identifier associated with the device generating the discovery signal.
The method of claim 1,

Prior to transmitting the discovery signal, receiving a request signal from the counterpart device,

The request signal includes a PDCP packet including a relay device search indicator related to the relay device transmitting the discovery signal, a MAC packet including the relay device search indicator, a physical layer packet including a relay device search identifier, and the relay device. And at least one of a resource allocation indicator masked as a discovery indicator and a relay request message configured in a service layer signaling format.
The method of claim 7, wherein the request signal,

PDCP packet including a group discovery request indicator, a MAC packet including the group discovery request indicator, a physical layer packet including a group discovery request identifier, a resource allocation indicator masked by the group discovery request indicator, and a service layer signaling format And at least one of a group search request message.
The method of claim 1, wherein the request signal,

And at least one of a device identifier, a group identifier, a PLMN identifier, APN information, and information on a physical channel used to transmit the discovery signal associated with the device transmitting the request signal.
The method of claim 1, wherein the additional information,

And at least one of a device identifier, a group identifier, a PLMN identifier, APN information, a service identifier, service information, group information, and physical channel information used for transmission of the discovery signal related to the device transmitting the discovery signal. Search method.
In a search method for communication between devices,

Receiving a discovery signal including discovery information from the external device;

Checking the search information obtained from the search signal;

Transmitting a request signal for requesting additional information required for discovery based on the discovery information to the counterpart device;

And receiving a confirmation signal including the additional information from the counterpart device in response to the request signal.
An apparatus for performing device-to-device communication,

A processor for generating a discovery signal including discovery information and selecting a transmission resource to transmit the discovery signal;

A transmitter for transmitting the discovery signal through the selected transmission resource;

It includes a receiving unit for receiving a request signal for requesting additional information related to the search from the external device receiving the search signal,

And the processor controls the transmitter to transmit a confirmation signal including the requested additional information to the counterpart device.
An apparatus for performing device-to-device communication,

A receiving unit which receives a search signal including search information from an external device,

A processor for identifying the search information obtained from the search signal;

A transmitter which transmits a request signal for requesting additional information necessary for searching based on the search information to the counterpart device;

The processor, in response to the request signal, characterized in that for receiving the confirmation signal containing the additional information from the external device via the receiving unit.
In a communication method between devices,

When an event occurs in a device, determining whether event information indicating the occurrence of the event can be transmitted to other devices within a predetermined range within a predetermined time;

Transmitting the event information through a device-to-device direct communication method when the event information can be transmitted as a result of the determination;

If the transmission of the event information is impossible as a result of the determination, transmitting the event information to the other devices according to a local transmission method via a base station.
An apparatus for communicating between devices,

A control unit for determining whether or not event information indicating the occurrence of the event can be transmitted to other devices within a predetermined range in a predetermined time when an event occurs in a device;

If it is possible to transmit the event information as a result of the determination, the event information is transmitted in a direct communication method between devices, and if it is impossible to transmit the event information as a result of the determination, the event information is transmitted to the other devices via a base station. Communication apparatus between devices including a transmitting and receiving unit for transmitting in accordance with a local transmission method.